Organometallic compound and organic light-emitting device including the same

ABSTRACT

An organometallic compound represented by Formula 1: 
       M(L 1 ) n1 (L 2 ) n2 ,  Formula 1
 
     wherein M is selected from iridium (Ir), platinum (Pt), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), thulium (Tm), and rhodium (Rd), and wherein L 1  is a ligand represented by Formula 2A and L 2  is a ligand represented by Formula 2B, and wherein L 1  and L 2  in Formula 1 are different from each other,

RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2014-0129516, filed on Sep. 26, 2014, in the KoreanIntellectual Property Office, and all the benefits accruing therefromunder 35 U.S.C. §119, the content of which is incorporated herein in itsentirety by reference.

BACKGROUND

1. Field

The present disclosure relates to an organometallic compound and anorganic light-emitting device including the same.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices that have wideviewing angles, high contrast ratios, short response times, andexcellent brightness, driving voltage, and response speedcharacteristics, and produce full-color images.

In an example, an organic light-emitting device includes an anode, acathode, and an organic layer that is disposed between the anode and thecathode and includes an emission layer. A hole transport region may bedisposed between the anode and the emission layer, and an electrontransport region may be disposed between the emission layer and thecathode. Holes provided from the anode may move toward the emissionlayer through the hole transport region, and electrons provided from thecathode may move toward the emission layer through the electrontransport region. The holes and the electrons are recombined in theemission layer to produce excitons. These excitons change from anexcited state to a ground state, thereby generating light.

Nonetheless there remains a need for an improved material for theemission layer.

SUMMARY

An embodiment relates to an organometallic compound and an organiclight-emitting device including the same.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description.

An aspect of an exemplary embodiment provides an organometallic compoundrepresented by Formula 1:

M(L₁)_(n1)(L₂)_(n2),  Formula 1

wherein M in Formula 1 is selected from iridium (Ir), platinum (Pt),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), thulium (Tm), and rhodium (Rd),

wherein L₁ is a ligand represented by Formula 2A and L₂ is a ligandrepresented by Formula 2B, and wherein L₁ and L₂ in Formula 1 aredifferent from each other,

wherein in Formula 2A, Y₁ to Y₄ are each independently carbon (C) ornitrogen (N), Y₁ and Y₂ are linked to each other via a single bond or adouble bond, and Y₃ and Y₄ are linked to each other via a single bond ora double bond,

wherein in Formulas 2A and 2B,

CY₁ to CY₃ are each independently selected from a C₅-C₆₀ cyclic groupand a C₁-C₆₀ heterocyclic group, and CY₁ and CY₂ are optionally furtherlinked to each other via a first linking group,

-   -   R₁ to R₃ in Formula 2B are each independently selected from        -   a C₁-C₁₀ alkyl group; and        -   a C₁-C₁₀ alkyl group, which is substituted with at least one            selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,            —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group,            a nitro group, an amino group, an amidino group, a hydrazine            group, a hydrazone group, a carboxylic acid or a salt            thereof, a sulfonic acid or a salt thereof, a phosphoric            acid or a salt thereof, and a C₁-C₁₀ alkyl group,    -   Z₁, Z₂, and R₁₁ to R₁₄ in Formulas 2A and 2B are each        independently selected from a hydrogen, a deuterium, —F, —Cl,        —Br, —I, —SF₅, a hydroxyl group, a nitro group, an amino group,        an amidino group, a hydrazine group, a hydrazone group, a        carboxylic acid or a salt thereof, a sulfonic acid or a salt        thereof, a phosphoric acid or a salt thereof, a substituted or        unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted        C₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀        alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxy        group, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, a        substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, a        substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a        substituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, a        substituted or unsubstituted C₆-C₆₀ aryl group, a substituted or        unsubstituted C₆-C₆₀ aryloxy group, a substituted or        unsubstituted C₆-C₆₀ arylthio group, a substituted or        unsubstituted C₁-C₆₀ heteroaryl group, a substituted or        unsubstituted monovalent non-aromatic condensed polycyclic        group, a substituted or unsubstituted monovalent non-aromatic        condensed heteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅),        —B(Q₆)(Q₇), and —P(═O)(Q₈)(Q₉), wherein R₁₂ in Formula 2B is not        a hydrogen or a —CH₃,    -   a1 and a2 are each independently selected from 1, 2, 3, 4, and        5, and when a1 is 2 or more, each Z₁ of a plurality of Z₁ may be        identical or different from each other, and when a2 is 2 or        more, each Z₂ of a plurality of Z₂ may be identical or different        from each other, and    -   b1 in Formula 2B is selected from 1, 2, 3, and 4, and

wherein in Formula 1, n1 and n2 are each independently 1 or 2, with theproviso that the sum of n1 and n2 is 2 or 3;

wherein * and *′ in Formulas 2A and 2B are each a binding site to M inFormula 1; and

wherein at least one of substituents of the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arythio group,the substituted C₁-C₆₀ heteroaryl group, the substituted a monovalentnon-aromatic condensed polycyclic group, and the substituted monovalentnon-aromatic condensed heteropolycyclic group is selected from

-   -   a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,        —CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino        group, an amidino group, a hydrazine group, a hydrazone group, a        carboxylic acid or a salt thereof, a sulfonic acid or a salt        thereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl        group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a        C₁-C₆₀ alkoxy group;    -   a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl        group, and a C₁-C₆₀ alkoxy group, each substituted with at least        one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,        —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a        nitro group, an amino group, an amidino group, a hydrazine        group, a hydrazone group, a carboxylic acid or a salt thereof, a        sulfonic acid or a salt thereof, a phosphoric acid or a salt        thereof, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl        group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl        group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀        arylthio group, a C₁-C₆₀ heteroaryl group, a monovalent        non-aromatic condensed polycyclic group, a monovalent        non-aromatic condensed heteropolycyclic group, —N(Q₁₁)(Q₁₂),        —Si(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), and —P(═O)(Q₁₈)(Q₁₉);    -   a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a        C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a        C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio        group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic        condensed polycyclic group, and a monovalent non-aromatic        condensed heteropolycyclic group; and    -   a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a        C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a        C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio        group, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic        condensed polycyclic group, and a monovalent non-aromatic        condensed heteropolycyclic group, each substituted with at least        one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,        —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a        nitro group, an amino group, an amidino group, a hydrazine        group, a hydrazone group, a carboxylic acid or a salt thereof, a        sulfonic acid or a salt thereof, a phosphoric acid or a salt        thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀        alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,        a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a        C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀        aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl        group, a monovalent non-aromatic condensed polycyclic group, a        monovalent non-aromatic condensed heteropolycyclic group,        —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅) —B(Q₂₆)(Q₂₇), and        —P(═O)(Q₂₈)(Q₂₉); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅)        —B(Q₃₆)(Q₃₇), and —P(═O)(Q₃₈)(Q₃₉);        -   wherein Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ to Q₃₉ are            each independently selected from a hydrogen, a deuterium,            —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro            group, an amino group, an amidino group, a hydrazine group,            a hydrazone group, a carboxylic acid or a salt thereof, a            sulfonic acid or a salt thereof, a phosphoric acid or a salt            thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a            C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀            cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀            cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a            C₆-C₆₀ aryl group, a C₆-C₆₀ aryl group substituted with at            least one selected from a C₁-C₆₀ alkyl group and a C₆-C₆₀            aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,            a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic            condensed polycyclic group, and a monovalent non-aromatic            condensed heteropolycyclic group.

Another aspect provides an organic light-emitting device including: afirst electrode; a second electrode; and an organic layer that isdisposed between the first electrode and the second electrode and whichincludes an emission layer, wherein the emission layer includes theorganometallic compound represented by Formula 1.

The organometallic compound may be included in the emission layer, andthe organometallic compound included in the emission layer may act as adopant, and the emission layer may further include a host.

Also disclosed is a method of manufacturing an organic light-emittingdevice, the method including: providing a first electrode; a secondelectrode; and an organic layer that is disposed between the firstelectrode and the second electrode and which comprises an emissionlayer, wherein the emission layer comprises the organometallic compoundof claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the exemplary embodiments,taken in conjunction with FIG. 1 which is a schematic view of anembodiment of an organic light-emitting device.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments, examplesof which are illustrated in the accompanying drawings, wherein likereference numerals refer to like elements throughout. In this regard,the present exemplary embodiments may have different forms and shouldnot be construed as being limited to the descriptions set forth herein.Accordingly, the exemplary embodiments are merely described below, byreferring to the figures, to explain aspects. As used herein, the term“and/or” includes any and all combinations of one or more of theassociated listed items. “Or” means “and/or.” Expressions such as “atleast one of,” when preceding a list of elements, modify the entire listof elements and do not modify the individual elements of the list.

It will be understood that when an element is referred to as being “on”another element, it can be directly on the other element or interveningelements may be present therebetween. In contrast, when an element isreferred to as being “directly on” another element, there are nointervening elements present.

It will be understood that, although the terms “first,” “second,”“third” etc. may be used herein to describe various elements,components, regions, layers and/or sections, these elements, components,regions, layers and/or sections should not be limited by these terms.These terms are only used to distinguish one element, component, region,layer or section from another element, component, region, layer orsection. Thus, “a first element,” “component,” “region,” “layer” or“section” discussed below could be termed a second element, component,region, layer or section without departing from the teachings herein.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms, including “at least one,” unless the content clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

Furthermore, relative terms, such as “lower” or “bottom” and “upper” or“top,” may be used herein to describe one element's relationship toother elements as illustrated in the Figures. It will be understood thatrelative terms are intended to encompass different orientations of thedevice in addition to the orientation depicted in the Figures. Forexample, if the device in one of the figures is turned over, elementsdescribed as being on the “lower” side of other elements would then beoriented on “upper” sides of the other elements. The exemplary term“lower,” can therefore, encompasses both an orientation of “lower” and“upper,” depending on the particular orientation of the FIGURE.Similarly, if the device in one of the figures is turned over, elementsdescribed as “below” or “beneath” other elements would then be oriented“above” the other elements. The exemplary terms “below” or “beneath”can, therefore, encompass both an orientation of above and below.

“About” or “approximately” as used herein is inclusive of the statedvalue and means within an acceptable range of deviation for theparticular value as determined by one of ordinary skill in the art,considering the measurement in question and the error associated withmeasurement of the particular quantity (i.e., the limitations of themeasurement system). For example, “about” can mean within one or morestandard deviations, or within ±30%, 20%, 10%, 5% of the stated value.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure belongs. It willbe further understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and thepresent disclosure, and will not be interpreted in an idealized oroverly formal sense unless expressly so defined herein.

Exemplary embodiments are described herein with reference to crosssection illustrations that are schematic illustrations of idealizedembodiments. As such, variations from the shapes of the illustrations asa result, for example, of manufacturing techniques and/or tolerances,are to be expected. Thus, embodiments described herein should not beconstrued as limited to the particular shapes of regions as illustratedherein but are to include deviations in shapes that result, for example,from manufacturing. For example, a region illustrated or described asflat may, typically, have rough and/or nonlinear features. Moreover,sharp angles that are illustrated may be rounded. Thus, the regionsillustrated in the figures are schematic in nature and their shapes arenot intended to illustrate the precise shape of a region and are notintended to limit the scope of the present claims.

“Alkenyl” means a straight or branched chain, monovalent hydrocarbongroup having at least one carbon-carbon double bond (e.g., ethenyl(—HC═CH₂)).

“Alkoxy” means an alkyl group that is linked via an oxygen (i.e.,alkyl-O—), for example methoxy, ethoxy, and sec-butyloxy groups.

“Alkyl” as used herein means a straight or branched chain, saturated,monovalent hydrocarbon group (e.g., methyl or hexyl).

“Alkynyl” means a straight or branched chain, monovalent hydrocarbongroup having at least one carbon-carbon triple bond (e.g., ethynyl).

“Amino” has the general formula —N(R)₂, wherein each R is independentlyhydrogen, a C1 to C6 alkyl, or a C6 to C12 aryl.

“Amidino” means a group of the formula —C(NR¹R²)═NR³, wherein each ofR¹, R², and R³ is independently hydrogen, a C1 to C8 alkyl, or a C6 toC12 aryl.

“Aryloxy” means an aryl moiety that is linked via an oxygen (i.e.,—O-aryl). An aryloxy group includes a C6 to C30 aryloxy group, andspecifically a C6 to C18 aryloxy group. Non-limiting examples includephenoxy, naphthyloxy, and tetrahydronaphthyloxy.

“Arylthio” means an aryl moiety that is linked via a sulfur (i.e.,—S-aryl). Examples of arylthio groups include phenylthio, naphthylthio.

“Cycloalkenyl” means a monovalent group having one or more rings and oneor more carbon-carbon double bond in the ring, wherein all ring membersare carbon (e.g., cyclopentyl and cyclohexyl).

“Cycloalkyl” means a monovalent group having one or more saturated ringsin which all ring members are carbon (e.g., cyclopentyl and cyclohexyl).

The prefix “hetero” means that the compound or group includes at leastone a heteroatom (e.g., 1, 2, or 3 heteroatom(s)), wherein theheteroatom(s) is each independently N, O, S, Si, or P.

An organometallic compound according to an embodiment is represented byFormula 1:

M(L₁)_(n1)(L₂)_(n2),  Formula 1

wherein L₁ is a ligand represented by Formula 2A, and L₂ is a ligandrepresented by Formula 2B:

wherein L₁ and L₂ in Formula 1 are different from each other, and * and*′ in Formulas 2A and 2B are binding sites to M in Formula 1.

M in Formula 1 may be selected from iridium (Ir), platinum (Pt), osmium(Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), thulium (Tm), and rhodium (Rd).

For example, M in Formula 1 may be Ir or Pt.

In Formula 2A, Y₁ to Y₄ are each independently carbon (C) or nitrogen(N), Y₁ and Y₂ are linked to each other via a single bond or a doublebond, and Y₃ and Y₄ are linked to each other via a single bond or adouble bond.

In some embodiments, in Formula 2A, Y₁ may be N and Y₂ to Y₄ may be C,but they are not limited thereto.

In Formulas 2A and 2B, CY₁ to CY₃ may be each independently selectedfrom a C₅-C₆₀ cyclic group and a C₁-C₆₀ heterocyclic group, and CY₁ andCY₂ may be optionally further linked to each other via a first linkinggroup. The C₅-C₆₀ cyclic group and the C₁-C₆₀ heterocyclic group mayeach be “a monocyclic group” or “polycyclic group.”

According to an embodiment, CY₁ to CY₃ in Formulas 2A and 2B may be eachindependently selected from a benzene, a naphthalene, a fluorene, aspiro-fluorene, an indene, a pyrrole, a thiophene, a furan, animidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, anisooxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, aquinoline, an isoquinoline, a benzoquinoline, a quinoxalaine, aquinazoline, a carbazole, a benzoimidazole, a benzofuran, abenzothiophene, an isobenzothiophene, a benzoxazole, an isobenzoxazole,a triazole, a tetrazole, an oxadiazole, a triazine, a dibenzofuran, adibenzothiophene, and 5,6,7,8-tetrahydroisoquinoline.

In some embodiments, in Formulas 2A and 2B, CY₁ may be selected from apyridine, a pyrimidine, a pyrazine, a triazine, a triazole, animidazole, a pyrazole, and 5,6,7,8-tetrahydroisoquinoline, CY₂ may beselected from a benzene, a pyridine, a pyrimidine, a pyrazine, atriazine, a carbazole, a dibenzofuran, and a dibenzothiophene, and CY₃may be selected from a benzene, a carbazole, a dibenzofuran, and adibenzothiophene.

CY₁ and CY₂ in Formula 2A may be optionally further linked to each othervia a first linking group, and the first linking group may be selectedfrom linking groups represented by Formula 6:

*—(Z₃₁)_(b10)—*′,  Formula 6

wherein Z₃₁ in Formula 6 may be selected from *—O—*′, *—S—*′,*—N(Q₄₁)-*′, *—C(Q₄₂)(Q₄₃)-*′, *—C(Q₄₄)═C(Q₄₅)-*′ and

wherein Q₄₁ to Q₄₉ may be each independently selected from

-   -   a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a        cyano group, a nitro group, an amino group, an amidino group, a        hydrazine group, a hydrazone group, a carboxylic acid or a salt        thereof, a sulfonic acid or a salt thereof, a phosphoric acid or        a salt thereof, a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;    -   a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted        with at least one selected from a deuterium, —F, —Cl, —Br, —I, a        hydroxyl group, a cyano group, a nitro group, an amino group, an        amidino group, a hydrazine group, a hydrazone group, a        carboxylic acid or a salt thereof, a sulfonic acid or a salt        thereof, a phosphoric acid or a salt thereof, a phenyl group, a        naphthyl group, a pyridinyl group, and a pyrimidinyl group; and    -   a phenyl group, a naphthyl group, a pyridinyl group, and a        pyrimidinyl group; and

wherein b10 is selected from an integer of 1 to 10, and when b10 is 2 ormore, a plurality of Z₃₁ may be identical or different.

For example, Q₄₁ to Q₄₉ in Formula 6 may be each independently selectedfrom a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a phenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup; and

a phenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup, but they are not limited thereto.

For example, CY₁ and CY₂ in Formula 2 are optionally further linked toeach other via a first linking group, and the first linking group isrepresented by *—C(Q₄₄)═C(Q₄₅)-*′ or

(that is, b10 in Formula 6 is 1), and Q₄₄ to Q₄₉ may be eachindependently selected from a hydrogen, a C₁-C₁₀ alkyl group, and aC₁-C₁₀ alkoxy group, but they are not limited thereto.

R₁ to R₃ in Formula 2B are each independently selected from

a C₁-C₁₀ alkyl group; and

a C₁-C₁₀ alkyl group, substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, and a C₁-C₁₀ alkyl group.

In some embodiments, R₁ to R₃ in Formula 2B may be each independentlyselected from

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, atert-pentyl group, an n-hexyl group, an isohexyl group, a sec-hexylgroup, a tert-hexyl group, an n-heptyl group, an isoheptyl group, asec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctylgroup, a sec-octyl group, a tert-octyl group, an n-nonyl group, anisononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group,an isodecyl group, a sec-decyl group, and a tert-decyl group, each ofwhich is unsubstituted; and

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, atert-pentyl group, an n-hexyl group, an isohexyl group, a sec-hexylgroup, a tert-hexyl group, an n-heptyl group, an isoheptyl group, asec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctylgroup, a sec-octyl group, a tert-octyl group, an n-nonyl group, anisononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group,an isodecyl group, a sec-decyl group, and a tert-decyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,and a C₁-C₁₀ alkyl group.

In some embodiments, R₁ to R₃ in Formula 2B may be each independentlyselected from

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, and atert-pentyl group, each of which is unsubstituted; and

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, and atert-pentyl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, and a C₁-C₁₀ alkyl group.

In some embodiments, R₁ to R₃ in Formula 2B may be each independentlyselected from a C₁-C₄ alkyl group, and a C₁-C₄ alkyl group substitutedwith at least one deuterium.

In some embodiments, R₁ to R₃ in Formula 2B may be each independentlyselected from —CH₃, —CH₂CH₃, —CD₃, —CD₂H, —CDH₂, —CH₂CD₃, and —CD₂CH₃,but they are not limited thereto.

In some embodiments, R₁ to R₃ in Formula 2B may be identical.

Z₁, Z₂, and R₁₁ to R₁₄ in Formulas 2A and 2B may be each independentlyselected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, —SF₅, ahydroxyl group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and—P(═O)(Q₈)(Q₉), and wherein R₁₂ in Formula 2B is not a hydrogen or a—CH₃.

In some embodiments, Z₁, Z₂, R₁₁, R₁₃, and R₁₄ in Formulas 2A and 2B areeach independently selected from

a hydrogen, a deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₁-C₁₄ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, and amonovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄ arylgroup, a C₁-C₁₄ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄ arylgroup, a C₁-C₁₄ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, each substituted with at least one selected froma deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₁-C₁₄heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group; and

—N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and —P(═O)(Q₈)(Q₉),

wherein Q₁ to Q₉ may be each independently selected from a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₆-C₁₄ aryl groupsubstituted with at least one selected from a C₁-C₂₀ alkyl group and aC₆-C₁₄ aryl group, a C₁-C₁₄ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.

In some embodiments, Z₁, Z₂, R₁₁, R₁₃, and R₁₄ in Formulas 2A and 2B maybe each independently selected from a hydrogen, a deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, —SF, a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxygroup;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₁H, —CFH₁, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornenyl group, a cyclopentenyl group,a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group, each substituted with at leastone selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂,—CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group; and

—B(Q₆)(Q₇) and —P(═O)(Q₈)(Q₉),

wherein Q₆ to Q₉ may be each independently selected from a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, a triazinyl group, and acarbazolyl group; and a phenyl group and a naphthyl group, eachsubstituted with at least one selected from a C₁-C₂₀ alkyl group, aphenyl group, and a naphthyl group, but they are not limited thereto.

In some embodiments, Z₁, Z₂, R₁₁, R₁₃, and R₁₄ in Formulas 2A and 2B maybe each independently selected from a hydrogen, a deuterium, —F, a cyanogroup, a nitro group, —SF₅, a methyl group, an ethyl group, an n-propylgroup, an isopropyl group, an n-butyl group, an isobutyl group, asec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a sec-pentyl group, a tert-pentyl group, an n-hexyl group, anisohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptylgroup, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, ann-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group,an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonylgroup, an n-decyl group, an isodecyl group, a sec-decyl group, atert-decyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group, each of which is unsubstituted;

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, atert-pentyl group, an n-hexyl group, an isohexyl group, a sec-hexylgroup, a tert-hexyl group, an n-heptyl group, an isoheptyl group, asec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctylgroup, a sec-octyl group, a tert-octyl group, an n-nonyl group, anisononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group,an isodecyl group, a sec-decyl group, a tert-decyl group, a methoxygroup, an ethoxy group, a propoxy group, a butoxy group, a pentoxygroup, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup, each substituted with at least one selected from a deuterium, —F,—CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a cyano group, a nitro group, aC₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group; and

—B(Q₆)(Q₇) and —P(═O)(Q₈)(Q₉),

wherein Q₆ to Q₉ may be each independently selected from

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, and anaphthyl group;

a phenyl group and a naphthyl group, each substituted with at least oneselected from a C₁-C₁₀ alkyl group, a phenyl group, and a naphthylgroup, but they are not limited thereto.

In some embodiments, R₁₂ in Formula 2B may be selected from

a C₂-C₂₀ alkyl group and a C₂-C₂₀ alkoxy group;

a methyl group and a methoxy group, each substituted with at least oneselected from a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₁₄ aryl group, a C₁-C₁₄ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group;

a C₂-C₂₀ alkyl group and a C₂-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₁-C₁₄ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, and amonovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄ arylgroup, a C₁-C₁₄ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄ arylgroup, a C₁-C₁₄ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group, each substituted with at least one selected froma deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₁-C₁₄heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group; and

—N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and —P(═O)(Q₈)(Q₉),

wherein Q₁ to Q₉ may be each independently selected from a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₆-C₁₄ aryl groupsubstituted with at least one selected from a C₁-C₂₀ alkyl group and aC₆-C₁₄ aryl group, a C₁-C₁₄ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.

In some embodiments, R₁₂ in Formula 2B may be selected from

a C₂-C₂₀ alkyl group and a C₂-C₂₀ alkoxy group;

a methyl group and a methoxy group, each substituted with at least oneselected from a cyclopentyl group, a cyclohexyl group, a cycloheptylgroup, a cyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup;

a C₂-C₂₀ alkyl group and a C₂-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornenyl group, a cyclopentenyl group,a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group, each substituted with at leastone selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂,—CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group; and

—B(Q₆)(Q₇) and —P(═O)(Q₈)(Q₉),

wherein Q₆ to Q₉ may be each independently selected from

a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a pyridinyl group, a pyrimidinyl group, a triazinyl group, and acarbazolyl group; and

a phenyl group and a naphthyl group, each substituted with at least oneselected from a C₁-C₂₀ alkyl group, a phenyl group, and a naphthylgroup, but they are not limited thereto.

In some embodiments, R₁₂ in Formula 2B may be selected from

an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group,an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, a tert-decyl group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group;

a methyl group and a methoxy group, each substituted with at least oneselected from a cyclopentyl group, a cyclohexyl group, a cycloheptylgroup, a cyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup; and

an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group,an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, a tert-decyl group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group, each substituted with at least oneselected from a deuterium, —F, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, acyano group, a nitro group, a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group,a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup.

In some embodiments, Z₁, Z₂, R₁₁, R₁₃, and R₁₄ in Formulas 2A and 2B maybe each independently selected from a hydrogen, a deuterium, —F, a cyanogroup, a nitro group, —SF₅, —CH₃, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, groups represented by Formulas 9-1 to 9-17, and groupsrepresented by Formulas 10-1 to 10-16 illustrated, and

R₁₂ in Formula 2B may be selected from groups represented by Formulas9-1 to 9-17 and groups represented by Formulas 10-1 to 10-16, but theyare not limited thereto:

wherein a1 and a2 in Formula 2A may be each independently selected from1, 2, 3, 4, and 5, and when a1 is 2 or more, a plurality of Z₁ may beidentical or different, and when a2 is 2 or a plurality of Z₂ may beidentical or different. For example, a1 and a2 may each be 1, 2, or 3,but they are not limited thereto.

In Formula 2B, b1 may be selected from 1, 2, 3, and 4, and when b1 is 2or more, a plurality of R₁₄ may be identical or different. For example,b1 may be 1 or 2, but is not limited thereto.

The descriptions for R₁₅ to R₁₇ may be the same as defined in connectionwith R₁₄.

In Formula 1, n1 and n2 are each independently 1 or 2, and the sum of n1and n2 is 2 or 3.

For example, M may be Ir and the sum of n1 and n2 may be 3; or M may bePt and the sum of n1 and n2 may be 2.

In some embodiments, n2 in Formula 1 may be 1.

The organometallic compound represented by Formula 1 may be neutral,i.e., not a salt consisting of an ionic pair.

For example, L₁ in Formula 1 may be selected from ligands represented byFormula 2-1 to ligands represented by Formula 2-112:

The descriptions for Z₁ and Z₂ in Formulas 2-1 to 2-112 are the same asdefined above.

The descriptions for Z_(1a) and Z_(1b) are the same as explained inconnection with Z₁,

The descriptions for Z_(2a), Z_(2b), and Z_(2c) are the same asexplained in connection with Z₂, aa2 and ab2 are each independently 1 or2, aa3 and ab3 are each independently selected from 1, 2, and 3, aa4 andab4 may be each independently selected from, 1, 2, 3, and 4, and * and*′ indicate binding sites to a neighboring atom.

For example, Z₁, Z₂, Z_(1a), Z_(1b), Z_(2a), Z_(2b), and Z₂ in Formulas2-1 to 2-112 may be each independently selected from

a hydrogen, a deuterium, —F, a cyano group, a nitro group, —SF₅, amethyl group, an ethyl group, an n-propyl group, an isopropyl group, ann-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group,an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentylgroup, an n-hexyl group, an isohexyl group, a sec-hexyl group, atert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptylgroup, a tert-heptyl group, an n-octyl group, an isooctyl group, asec-octyl group, a tert-octyl group, an n-nonyl group, an isononylgroup, a sec-nonyl group, a tert-nonyl group, an n-decyl group, anisodecyl group, a sec-decyl group, a tert-decyl group, a methoxy group,an ethoxy group, a propoxy group, a butoxy group, and a pentoxy group;

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, atert-pentyl group, an n-hexyl group, an isohexyl group, a sec-hexylgroup, a tert-hexyl group, an n-heptyl group, an isoheptyl group, asec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctylgroup, a sec-octyl group, a tert-octyl group, an n-nonyl group, anisononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group,an isodecyl group, a sec-decyl group, a tert-decyl group, a methoxygroup, an ethoxy group, a propoxy group, a butoxy group, and a pentoxygroup, each substituted with at least one selected from a deuterium, —F,—CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a cyano group, a nitro group,and a C₁-C₁₀ alkyl group; and

a group represented by one of Formulas 10-1 to 10-16, but they are notlimited thereto.

For example, L₁ in Formula 1 may be a ligand represented by one ofFormulas 2-1 and 2-112, but is not limited thereto.

According an embodiment, L₁ in Formula 1 may be selected from ligandsrepresented by Formulas 2-1(1) to 2-1(18), but is not limited thereto:

wherein in Formulas 2-1(1) to 2-1(18), the descriptions for Z₁ and Z₂are the same as explained above, the descriptions for Z_(1a), Z_(1b),Z_(1c), and Z_(1d) are the same as explained in connection with Z₁, andThe descriptions for Z_(2a), Z_(2b), Z_(2c), and Z_(2d) are the same asexplained in connection with Z₂, wherein Z₁, Z₂, Z_(1a), Z_(1b), Z_(1c),Z_(1d), Z_(2a), Z_(2b), Z_(2c), and Z_(2d) are not hydrogens, and * and*′ indicate binding sites to M.

For example, Z₁, Z₂, Z_(1a), Z_(1b), Z_(1c), Z_(1d), Z_(2a), Z_(2b),Z_(2c), and Z_(2d) in Formulas 2-1(1) to 2-1(8) may be eachindependently selected from

a deuterium, —F, a cyano group, a nitro group, —SF₅, a methyl group, anethyl group, an n-propyl group, an isopropyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, a tert-decyl group, a methoxy group, an ethoxy group, apropoxy group, a butoxy group, and a pentoxy group;

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, atert-pentyl group, an n-hexyl group, an isohexyl group, a sec-hexylgroup, a tert-hexyl group, an n-heptyl group, an isoheptyl group, asec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctylgroup, a sec-octyl group, a tert-octyl group, an n-nonyl group, anisononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group,an isodecyl group, a sec-decyl group, a tert-decyl group, a methoxygroup, an ethoxy group, a propoxy group, a butoxy group, and a pentoxygroup, each substituted with at least one selected from a deuterium, —F,—CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a cyano group, a nitro group,and a C₁-C₁₀ alkyl group; and

a group represented by one of Formulas 10-1 to 10-16, but they are notlimited thereto.

In some embodiments, L₂ in Formula 1 may be selected from ligandsrepresented by Formulas 2B-1 to 2B-12:

In Formulas 2B-1 to 2B-12, R₁, R₂, R₃, and R₁₁ to R₁₄ are alreadyexplained above, and the descriptions for R₁₅ to R₁₇ are the same asexplained in connection with R₁₄. However, R₁₁ to R₁₇ in Formulas 2B-1to 2B-12 are not hydrogens.

For example, in Formulas 2B-1 to 2B-12, R₁ to R₃ may be eachindependently selected from

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, and atert-pentyl group; and

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, and atert-pentyl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, and a C₁-C₁₀ alkyl group.

R₁₁ and R₁₃ to R₁₇ may be each independently selected from

a deuterium, —F, a cyano group, a nitro group, —SF₅, a methyl group, anethyl group, an n-propyl group, an isopropyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, a tert-decyl group, a methoxy group, an ethoxy group, apropoxy group, a butoxy group, a pentoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group;

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butylgroup, an n-pentyl group, an isopentyl group, a sec-pentyl group, atert-pentyl group, an n-hexyl group, an isohexyl group, a sec-hexylgroup, a tert-hexyl group, an n-heptyl group, an isoheptyl group, asec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctylgroup, a sec-octyl group, a tert-octyl group, an n-nonyl group, anisononyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group,an isodecyl group, a sec-decyl group, a tert-decyl group, a methoxygroup, an ethoxy group, a propoxy group, a butoxy group, a pentoxygroup, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup, each substituted with at least one selected from a deuterium, —F,—CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a cyano group, a nitro group, aC₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group; and

—B(Q₆)(Q₇) and —P(═O)(Q₈)(Q₉),

wherein Q₆ to Q₉ may be each independently selected from

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, and anaphthyl group; and

a phenyl group and a naphthyl group, each substituted with at least oneselected from a C₁-C₁₀ alkyl group, a phenyl group, and a naphthylgroup.

R₁₂ may be selected from

an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group,an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, a tert-decyl group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group;

a methyl group and a methoxy group, each substituted with at least oneselected from a cyclopentyl group, a cyclohexyl group, a cycloheptylgroup, a cyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup; and

an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group,an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, a tert-decyl group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group, each substituted with at least oneselected from a deuterium, —F, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, acyano group, a nitro group, a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group,a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup, but they are not limited thereto.

In some embodiments, in Formulas 2B-1 to 2B-12,

R₁ to R₃ may be each independently selected from —CH₃, —CH₂CH₃, —CD₃,—CD₂H, —CDH₂, —CH₂CD₃, and —CD₂CH₃,

R₁₁, and R₁₃ to R₁₇ may be each independently selected from a deuterium,—F, a cyano group, a nitro group, —SF₅, —CH₃, —CD₃, —CD₂H, —CDH₂, —CF₃,—CF₂H, —CFH₂, groups represented by Formulas 9-1 to 9-17, and groupsrepresented by Formulas 10-1 to 10-16, and

R₁₂ may be selected from groups represented by Formulas 9-1 to 9-17 andgroups represented by Formulas 10-1 to 10-16, but they are not limitedthereto.

In some embodiments, in Formula 1,

M is Ir and the sum of n1 and n2 is 3; or M is Pt and the sum of n1 andn2 is 2,

L₁ may be selected from ligands represented by Formulas 2-1 to 2-112(for example, ligands represented by Formulas 2-1(1) to 2-1(18),

L₂ may be selected from ligands represented by Formulas 2B-1 to 2B-12,and

the organometallic compound represented by Formula 1 may be neutral, butis not limited thereto.

The organometallic compound may be one of Compounds 1 to 388, but is notlimited thereto:

L₂ in Formula 1 is a ligand represented by Formula 2B, which is aphenyl-pyridinyl based bidentate ligand. Accordingly, the organometalliccompound represented by Formula 1 has a highest occupied molecularorbital (“HOMO”) energy level, lowest unoccupied molecular orbital(“LUMO”) energy level, and T1 energy level which are appropriate for useas a material for an electric device, for example, a material for anorganic light-emitting device. Thus, an organic light-emitting deviceusing the organometallic compound represented by Formula 1 has excellentefficiency and lifespan characteristics.

R₁ to R₃ in Formula 2B are each independently a substituted orunsubstituted C₁-C₁₀ alkyl group and R₁₂ in Formula 2B is not a hydrogenand a methyl group. As such, the organometallic compound represented byFormula 1 may emit blue light, green light, or greenish blue light thatis shifted toward relatively shorter wavelengths, and a device, forexample, an organic light-emitting device, including the organometalliccompound may have long lifespan.

In Formula 2B, a silyl group bonds to the fifth position of a pyridinering (see Formula 2B). Due to the bonding, the organometallic compoundincluding the ligand represented by Formula 2B has excellent heatresistance and decomposition resistance characteristics. Accordingly, adevice, for example, an organic light-emitting device, including theorganometallic compound has high stability during manufacturing,preserving, and/or driving, and long lifespan.

For example, HOMO, LUMO, singlet (S₁) and triplet (T₁) energy levels ofsome of the organometallic compounds and Compound A′ were evaluated byusing a density functional theory (“DFT”) method of Gaussian program(structurally optimized at a level of B3LYP, 6-31 G(d,p)). Evaluationresults are shown in Table 1.

TABLE 1 S₁ energy T₁ energy Compound No. HOMO(eV) LUMO(eV) level (eV)level (eV) 6 −4.807 −1.180 2.880 2.624 14 −4.803 −1.175 2.881 2.624 51−4.776 −1.167 2.832 2.581 96 −4.803 −1.232 2.862 2.567 136 −4.830 −1.2942.815 2.563 189 −4.807 −1.180 2.880 2.624 219 −4.807 −1.180 2.880 2.624241 −4.767 −1.174 2.869 2.641 296 −4.756 −1.153 2.866 2.615 A′ −4.936−1.567 2.691 2.498

From Table 1, it is confirmed that absolute values of the HOMO energylevel and LUMO energy level of Compound A′ are greater than absolutevalues of the HOMO energy level and LUMO energy level of Compounds 6,14, 51, 96, 136, 189, 219, 241, and 296, and T₁ energy value of CompoundA′ is smaller than T₁ energy values of Compounds 6, 14, 51, 96, 136,189, 219, 241 and 296. Accordingly, the organometallic compoundrepresented by Formula 1 provides higher charge mobility than CompoundA′, and thus, an electric device, for example, an organic light-emittingdevice, including the organometallic compound represented by Formula 1may have excellent efficiency and lifespan characteristics. In addition,since the organometallic compound represented by Formula 1 provides awider color reproduction range than Compound A′, the use of theorganometallic compound represented by Formula 1 may enable productionof a high-quality organic light-emitting device.

Synthesis methods of the organometallic compound represented by Formula1 may be understood to one of ordinary skill in the art by referring toSynthesis Examples provided.

The organometallic compound represented by Formula 1 is suitable for usein an organic layer of an organic light-emitting device, for example,for use as a dopant in an emission layer of the organic layer. Thus,another aspect provides an organic light-emitting device that includes:a first electrode; a second electrode; and an organic layer that isdisposed between the first electrode and the second electrode andincluding an emission layer and at least one of the organometalliccompound represented by Formula 1.

The organic light-emitting device may have, due to the inclusion of anorganic layer including the organometallic compound represented byFormula 1, low driving voltage, high efficiency, high power, highquantum efficiency, long lifespan and excellent color coordinate.

The organometallic compound of Formula 1 may be used between a pair ofelectrodes of an organic light-emitting device to provide an emissionlayer. For example, the organometallic compound represented by Formula 1may be included in the emission layer. In this regard, theorganometallic compound may act as a dopant, and the emission layer mayfurther include a host, wherein an amount of the organometallic compoundrepresented by Formula 1 is less than an amount of the host.

In an embodiment, the organic layer, which includes at least oneorganometallic compound, may include two or more differentorganometallic compounds of Formula 1.

For example, the organic layer may include, as the organometalliccompound, only Compound 1. In this regard, Compound 1 may be present inan emission layer of the organic light-emitting device. In someembodiments, the organic layer may include, as the organometalliccompound, Compound 1 and Compound 2. In this regard, Compound 1 andCompound 2 may be present in a same layer, for example when an entiretyof Compound 1 and Compound 2 are present in a same emission layer.

The first electrode may be an anode, which is a hole injectionelectrode, and the second electrode may be a cathode, which is anelectron injection electrode; or the first electrode may be a cathode,which is an electron injection electrode, or the second electrode may bean anode, which is a hole injection electrode.

For example, the first electrode is an anode, and the second electrodeis a cathode, and the organic layer includes i) a hole transport regionthat is disposed between the first electrode and the emission layer andincludes at least one of a hole injection layer, a hole transport layer,and an electron blocking layer, and ii) an electron transport regionthat is disposed between the emission layer and the second electrode andincludes at least one selected from a hole blocking layer, an electrontransport layer, and an electron injection layer.

The term “organic layer” used herein refers to a single layer and/or aplurality of layers disposed between the first electrode and the secondelectrode of an organic light-emitting device. The “organic layer” mayinclude, in addition to an organic compound, an organometallic complexincluding metal.

FIG. 1 is a schematic view of an embodiment of an organic light-emittingdevice 10. Hereinafter, the structure of an organic light-emittingdevice according to an embodiment and a method of manufacturing anorganic light-emitting device according to an embodiment will be furtherdisclose with reference to FIG. 1. The organic light-emitting device 10includes a first electrode 11, an organic layer 15, and a secondelectrode 19, which are sequentially stacked.

In FIG. 1, a substrate may be additionally disposed under the firstelectrode 11 or above the second electrode 19. For use as the substrate,any substrate that is used in general organic light-emitting devices maybe used, and the substrate may be a glass substrate or transparentplastic substrate, each with excellent mechanical strength, thermalstability, transparency, surface smoothness, ease of handling, andwater-proofness.

The first electrode 11 may be formed by depositing or sputtering amaterial for forming the first electrode on the substrate. The firstelectrode 11 may be an anode. The material for the first electrode 11may be selected from materials with a high work function to allow holesbe easily provided. The first electrode 11 may be a reflective electrodeor a transmissive electrode. The material for the first electrode 11 maybe an indium tin oxide (“ITO”), indium zinc oxide (“IZO”), tin oxide(SnO₂), or zinc oxide (ZnO). In some embodiments, the material for thefirst electrode 11 may be metal, such as magnesium (Mg), aluminum (Al),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), ormagnesium-silver (Mg—Ag).

The first electrode 11 may have a single-layer structure or amulti-layer structure including two or more layers. For example, thefirst electrode 11 may have a three-layered structure of ITO/Ag/ITO, butthe structure of the first electrode 11 is not limited thereto.

An organic layer 15 is disposed on the first electrode 11.

The organic layer 15 may include a hole transport region, an emissionlayer, and an electron transport region.

The hole transport region may be disposed between the first electrode 11and the emission layer.

The hole transport region may include at least one of a hole injectionlayer, a hole transport layer, an electron blocking layer, and a bufferlayer.

The hole transport region may include only either a hole injection layeror a hole transport layer. According to another embodiment, the holetransport region may have a structure of hole injection layer/holetransport layer or hole injection layer/hole transport layer/electronblocking layer, which are sequentially stacked in this stated order fromthe first electrode 11.

When the hole transport region includes a hole injection layer (HIL),the hole injection layer may be formed on the first electrode 11 byusing any one of various methods, for example, vacuum deposition, spincoating, casting, or Langmuir-Blodgett (LB) deposition.

When a hole injection layer is formed by vacuum deposition, thedeposition conditions may vary according to a material that is used toform the hole injection layer, and the structure and thermalcharacteristics of the hole injection layer. For example, the depositionconditions may include a deposition temperature of about 100 to about500° C., a vacuum pressure of about 10⁻⁸ to about 10⁻³ torr, and adeposition rate of about 0.01 to about 100 Å/sec. However, thedeposition conditions are not limited thereto.

When the hole injection layer is formed using spin coating, coatingconditions may vary according to the material used to form the holeinjection layer, and the structure and thermal properties of the holeinjection layer. For example, a coating speed may be from about 2000revolutions per minute (“rpm”) to about 5000 rpm, and a temperature atwhich a heat treatment is performed to remove a solvent after coatingmay be from about 80° C. to about 200° C. However, the coatingconditions are not limited thereto.

Conditions for a hole transport layer and an electron blocking layer maybe understood by referring to conditions for forming the hole injectionlayer.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB, β-NPB, TPD, Spiro-TPD, Spiro-NPB,methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine(“TCTA”), polyaniline/dodecylbenzenesulfonic acid (“Pani/DBSA”),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (“PEDOT/PSS”),polyaniline/camphor sulfonicacid (“Pani/CSA”),polyaniline/poly(4-styrenesulfonate) (“PANI/PSS”), a compoundrepresented by Formula 201, and a compound represented by Formula 202:

wherein Ar₁₀₁ and Ar₁₀₂ in Formula 201 may be each independentlyselected from

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anacenaphthylene group, a fluorenylene group, a phenalenylene group, aphenanthrenylene group, an anthracenylene group, a fluoranthenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenylenegroup, a naphthacenylene group, a picenylene group, a perylenylenegroup, and a pentacenylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anacenaphthylene group, a fluorenylene group, a phenalenylene group, aphenanthrenylene group, an anthracenylene group, a fluoranthenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenylenegroup, a naphthacenylene group, a picenylene group, a perylenylenegroup, and a pentacenylene group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₁-C₁₀ heterocycloalkenylgroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group, and a monovalent non-aromatic condensedheteropolycyclic group.

In Formula 201, xa and xb may be each independently selected from 0, 1,2, 3, 4, and 5, and for example, may each be 0, 1, or 2. For example, xamay be 1 and xb may be 0, but xa and xb are not limited thereto.

R₁₀₁ to R₁₀₈, R₁₁₁ to R₁₁₉, and R₁₂₁ to R₁₂₄ in Formulas 201 and 202 maybe each independently selected from

a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₁₀ alkyl group (for example, a methyl group, an ethylgroup, a propyl group, a butyl group, a pentyl group, a hexyl group, andso on), and a C₁-C₁₀ alkoxy group (for example, a methoxy group, anethoxy group, a propoxy group, a butoxy group, a pentoxy group, and soon);

a C₁-C₁₀ alkyl group and a C₁-C₁₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, and a phosphoric acidgroup or a salt thereof;

a phenyl group, a naphthyl group, an anthracenyl group, a fluorenylgroup, and a pyrenyl group; and

a phenyl group, a naphthyl group, an anthracenyl group, a fluorenylgroup, and a pyrenyl group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₁₀ alkyl group, and a C₁-C₁₀ alkoxy group, but they are notlimited thereto.

R₁₀₉ in Formula 201 may be selected from

a phenyl group, a naphthyl group, an anthracenyl group, and a pyridinylgroup; and a phenyl group, a naphthyl group, an anthracenyl group, and apyridinyl group, each substituted with at least one selected from aphenyl group, a naphthyl group, an anthracenyl group and a pyridinylgroup; and a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, anaphthyl group, an anthracenyl group, and a pyridinyl group.

According to an embodiment, the compound represented by Formula 201 maybe represented by Formula 201A, but is not limited thereto:

R₁₀₁, R₁₁₁, R₁₁₂, and R₁₀₉ in Formula 201A may be understood byreferring to the description provided herein.

For example, the compound represented by Formula 201, and the compoundrepresented by Formula 202 may include compounds HT1 to HT20illustrated, but are not limited thereto.

A thickness of the hole transport region may be in a range of about 100angstroms (Å) to about 10,000 Å, for example, about 100 Å to about 1000Å. When the hole transport region includes both a hole injection layerand a hole transport layer, a thickness of the hole injection layer maybe in a range of about 100 Å to about 10000 Å, for example, about 100 Åto about 1000 Å, and a thickness of the hole transport layer may be in arange of about 50 Å to about 2000 Å, for example about 100 Å to about1500 Å. When the thicknesses of the hole transport region, the holeinjection layer, and the hole transport layer are within these ranges,satisfactory hole transporting characteristics may be obtained without asubstantial increase in driving voltage.

The hole transport region may further include, in addition to thesematerials, a charge-generation material for the improvement ofconductive properties. The charge-generation material may behomogeneously or non-homogeneously dispersed in the hole transportregion.

The charge-generation material may be, for example, a p-dopant. Thep-dopant may be one of a quinone derivative, a metal oxide, and a cyanogroup-containing compound, but is not limited thereto. Non-limitingexamples of the p-dopant are a quinone derivative, such astetracyanoquinonedimethane (“TCNQ”) or2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane (“F4-TCNQ”); ametal oxide, such as a tungsten oxide or a molybdenium oxide; and acyano group-containing compound, such as Compound HT-D1, but are notlimited thereto.

The hole transport region may include a buffer layer.

Also, the buffer layer may compensate for an optical resonance distanceaccording to a wavelength of light emitted from the emission layer, andthus, efficiency of a formed organic light-emitting device may beimproved.

Then, an emission layer (“EML”) may be formed on the hole transportregion by vacuum deposition, spin coating, casting, LB deposition, orthe like. When the emission layer is formed by vacuum deposition or spincoating, the deposition or coating conditions may be similar to thoseapplied to form the hole injection layer although the deposition orcoating conditions may vary according to the material that is used toform the emission layer.

In an embodiment, when the hole transport region includes an electronblocking layer, a material for the electron blocking layer may beselected from materials for the hole transport region described aboveand materials for a host to be explained later. However, the materialfor the electron blocking layer is not limited thereto. For example,when the hole transport region includes an electron blocking layer, amaterial for the electron blocking layer may be mCP, which will beexplained later.

The emission layer may include a host and a dopant, and the dopant mayinclude the organometallic compound represented by Formula 1.

The host may include at least one selected form TPBi, TBADN, AND (alsoreferred to as “DNA”), CBP, CDBP, TCP, mCP, Compound H50, and CompoundH51:

According to another embodiment, the host may further include a compoundrepresented by Formula 301,

wherein Ar_(m) and Ar₁₁₂ in Formula 301 may be each independentlyselected from

a phenylene group, a naphthylene group, a phenanthrenylene group, and apyrenylene group; and

a phenylene group, a naphthylene group, a phenanthrenylene group, and apyrenylene group, each substituted with at least one selected from aphenyl group, a naphthyl group, and an anthracenyl group.

Ar₁₁₃ to Ar₁₁₆ in Formula 301 may be each independently selected from

a C₁-C₁₀ alkyl group, a phenyl group, a naphthyl group, a phenanthrenylgroup, and a pyrenyl group; and

a phenyl group, a naphthyl group, a phenanthrenyl group, and a pyrenylgroup, each substituted with at least one selected from a phenyl group,a naphthyl group, and an anthracenyl group.

In Formula 301, g, h, i, and j in Formula 301 may be each independentlyselected from 0, 1, 2, 3, and 4, and may be, for example, 0, 1, or 2.

Ar₁₁₃ and Ar₁₁₆ in Formula 301 may be each independently selected from aC₁-C₁₀ alkyl group substituted with at least one selected from a phenylgroup, a naphthyl group, and an anthracenyl group;

a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl, aphenanthrenyl group, and a fluorenyl group;

a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group,a phenanthrenyl group, and a fluorenyl group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a phenyl group, a naphthyl group, ananthracenyl group, a pyrenyl group, a phenanthrenyl group, and afluorenyl group; and

but they are not limited thereto.

In some embodiments, the host may include a compound represented byFormula 302:

wherein Ar₁₂₂ to Ar₁₂₅ in Formula 302 are the same as described indetail in connection with Ar₁₁₃ in Formula 301.

In Formula 302, Ar₁₂₆ and Ar₁₂₇ may be each independently a C₁-C₁₀ alkylgroup (for example, a methyl group, an ethyl group, or a propyl group).

In Formula 302, k and l may be each independently an integer of 0 to 4.For example, k and l may be 0, 1, or 2.

The compound represented by Formula 301 and the compound represented byFormula 302 may include Compounds H1 to H42, but are not limitedthereto.

When the organic light-emitting device is a full color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, and a blue emission layer.According to another embodiment, due to a stack structure including ared emission layer, a green emission layer, and/or a blue emissionlayer, the emission layer may emit white light.

When the emission layer includes a host and a dopant, an amount of thedopant may be in a range of about 0.01 to about 15 parts by weight,based on 100 parts by weight of the host, but is not limited thereto.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, for example, about 200 Å to about 600 Å. When thethickness of the emission layer is within this range, excellentlight-emission characteristics may be obtained without a substantialincrease in driving voltage.

Then, an electron transport region may be disposed on the emissionlayer.

The electron transport region may include at least one selected from ahole blocking layer, an electron transport layer, and an electroninjection layer.

For example, the electron transport region may have a structure of holeblocking layer/electron transport layer/electron injection layer or astructure of electron transport layer/electron injection layer, but thestructure of the electron transport region is not limited thereto. Theelectron transport layer may have a single-layered structure or amulti-layer structure including two or more different materials.

Conditions for forming the hole blocking layer, the electron transportlayer, and the electron injection layer which constitute the electrontransport region may be understood by referring to the conditions forforming the hole injection layer.

When the electron transport layer includes a hole blocking layer, thehole blocking layer may include, for example, at least one of BCP,Bphen, and Balq but is not limited thereto.

A thickness of the hole blocking layer may be in a range of about 20 Åto about 1,000 Å, for example, about 30 Å to about 300 Å. When thethickness of the hole blocking layer is within these ranges, the holeblocking layer may have excellent hole blocking characteristics withouta substantial increase in driving voltage.

The electron transport layer may further include, in addition to theorganometallic compound represented by Formula 1, at least one selectedfrom BCP, Bphen, Alq₃, Balq, TAZ, and NTAZ.

According to another embodiment, the electron transport layer mayinclude at least one of ET1 and ET2, but are not limited thereto:

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. Whenthe thickness of the electron transport layer is within the rangedescribed above, the electron transport layer may have satisfactoryelectron transport characteristics without a substantial increase indriving voltage.

Also, the electron transport layer may further include, in addition tothe materials described above, a metal-containing material.

The metal-containing material may include a Li complex. The Li complexmay include, for example, Compound ET-D1 (lithium quinolate, LiQ) orET-D2:

The electron transport region may include an electron injection layer(“EIL”) that allows electrons to be easily provided from a secondelectrode 19.

The electron injection layer may include at least one selected from,LiF, NaCl, CsF, Li₂O, BaO, and LiQ.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, for example, about 3 Å to about 90 Å. When thethickness of the electron injection layer is within the range describedabove, the electron injection layer may have satisfactory electroninjection characteristics without a substantial increase in drivingvoltage.

The second electrode 19 is disposed on the organic layer 15. The secondelectrode 19 may be a cathode. A material for forming the secondelectrode 19 may be metal, an alloy, an electrically conductivecompound, and a combination thereof, which have a relatively low workfunction. For example, lithium (Li), magnesium (Mg), aluminum (Al),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), ormagnesium-silver (Mg—Ag) may be formed as the material for forming thesecond electrode 19. To manufacture a top emission type light-emittingdevice, a transmissive electrode formed using ITO or IZO may be used asthe second electrode 19.

Hereinbefore, the organic light-emitting device has been described withreference to FIG. 1, but is not limited thereto.

A C₁-C₆₀ alkyl group used herein refers to a linear or branchedaliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, anddetailed examples thereof are a methyl group, an ethyl group, a propylgroup, an isobutyl group, a sec-butyl group, a ter-butyl group, a pentylgroup, an iso-amyl group, and a hexyl group. A C₁-C₆₀ alkylene groupused herein refers to a divalent group having the same structure as theC₁-C₆₀ alkyl group.

A C₁-C₆₀ alkoxy group used herein refers to a monovalent grouprepresented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group), anddetailed examples thereof are a methoxy group, an ethoxy group, and anisopropyloxy group.

A C₂-C₆₀ alkenyl group used herein refers to a hydrocarbon group formedby substituting at least one carbon double bond in the middle orterminal of the C₂-C₆₀ alkyl group, and detailed examples thereof are anethenyl group, a prophenyl group, and a butenyl group. A C₂-C₆₀alkenylene group used herein refers to a divalent group having the samestructure as the C₂-C₆₀ alkenyl group.

A C₂-C₆₀ alkynyl group used herein refers to a hydrocarbon group formedby substituting at least one carbon triple bond in the middle orterminal of the C₂-C₆₀ alkyl group, and detailed examples thereof are anethynyl group, and a propynyl group. A C₂-C₆₀ alkynylene group usedherein refers to a divalent group having the same structure as theC₂-C₆₀ alkynyl group.

A C₃-C₁₀ cycloalkyl group used herein refers to a monovalent hydrocarbonmonocyclic group having 3 to 10 carbon atoms, and detailed examplesthereof are a cyclopropyl group, a cyclobutyl group, a cyclopentylgroup, a cyclohexyl group, and a cycloheptyl group. A C₃-C₁₀cycloalkylene group used herein refers to a divalent group having thesame structure as the C₃-C₁₀ cycloalkyl group.

A C₁-C₁₀ heterocycloalkyl group used herein refers to a monovalentmonocyclic group having at least one hetero atom selected from N, O, P,and S as a ring-forming atom and 1 to 10 carbon atoms, and detailedexamples thereof are a tetrahydrofuranyl group, and atetrahydrothiophenyl group. A C₁-C₁₀ heterocycloalkylene group usedherein refers to a divalent group having the same structure as theC₁-C₁₀ heterocycloalkyl group.

A C₃-C₁₀ cycloalkenyl group used herein refers to a monovalentmonocyclic group that has 3 to 10 carbon atoms and at least one doublebond in the ring thereof and does not have aromacity, and detailedexamples thereof are a cyclopentenyl group, a cyclohexenyl group, and acycloheptenyl group. A C₃-C₁₀ cycloalkenylene group used herein refersto a divalent group having the same structure as the C₃-C₁₀ cycloalkenylgroup.

A C₁-C₁₀ heterocycloalkenyl group used herein refers to a monovalentmonocyclic group that has at least one hetero atom selected from N, O,P, and S as a ring-forming atom, 1 to 10 carbon atoms, and at least onedouble bond in its ring. Detailed examples of the C₁-C₁₀heterocycloalkenyl group are a 2,3-hydrofuranyl group and a2,3-hydrothiophenyl group. A C₁-C₁₀ heterocycloalkenylene group usedherein refers to a divalent group having the same structure as theC₁-C₁₀ heterocycloalkenyl group.

A C₆-C₆₀ aryl group used herein refers to a monovalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms, and a C₆-C₆₀arylene group used herein refers to a divalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms. Detailedexamples of the C₆-C₆₀ aryl group are a phenyl group, a naphthyl group,an anthracenyl group, a phenanthrenyl group, a pyrenyl group, and achrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylene groupeach include two or more rings, the rings may be fused to each other.

A C₁-C₆₀ heteroaryl group used herein refers to a monovalent grouphaving a carboncyclic aromatic system that has at least one hetero atomselected from N, O, P, and S as a ring-forming atom, and 1 to 60 carbonatoms. A C₁-C₆₀ heteroarylene group used herein refers to a divalentgroup having a carbocyclic aromatic system that has at least one heteroatom selected from N, O, P, and S as a ring-forming atom, and 1 to 60carbon atoms. Examples of the C₁-C₆₀ heteroaryl group are a pyridinylgroup, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, and an isoquinolinyl group. Whenthe C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group eachinclude two or more rings, the rings may be fused to each other.

A C₆-C₆₀ aryloxy group used herein can be of the formula —OA₁₀₂, whereinA₁₀₂ is the C₆-C₆₀ aryl group, and a C₆-C₆₀ arylthio group can be of theformula —SA₁₀₃, wherein A₁₀₃ is the C₆-C₆₀ aryl group.

A monovalent non-aromatic condensed polycyclic group used herein refersto a monovalent group (for example, having 8 to 60 carbon atoms) thathas two or more rings condensed to each other, only carbon atoms as aring forming atom, and non-aromacity in the entire molecular structure.A detailed example of the monovalent non-aromatic condensed polycyclicgroup is a fluorenyl group. A divalent non-aromatic condensed polycyclicgroup used herein refers to a divalent group having the same structureas the monovalent non-aromatic condensed polycyclic group.

A monovalent non-aromatic condensed heteropolycyclic group used hereinrefers to a monovalent group (for example, having 1 to 60 carbon atoms)that has two or more rings condensed to each other, has a heteroatomselected from N, O P, and S, other than carbon atoms, as a ring formingatom, and has non-aromacity in the entire molecular structure. Anexample of the monovalent non-aromatic condensed heteropolycyclic groupis a carbazolyl group. A divalent non-aromatic condensedheteropolycyclic group used herein refers to a divalent group having thesame structure as the monovalent non-aromatic condensed heteropolycyclicgroup.

At least one of substituents of the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arythio group, the substituted C₁-C₆₀heteroaryl group, the substituted a monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from a deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, anda C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅),—B(Q₁₆)(Q₁₇), and —P(═O)(Q₁₈)(Q₁₉);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅),—B(Q₂₆)(Q₂₇), and —P(═O)(Q₂₈)(Q₂₉); and

—N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅) —B(Q₃₆)(Q₃₇), and —P(═O)(Q₃₈)(Q₃₉);

wherein Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ to Q₃₉ are eachindependently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from a C₁-C₆₀ alkyl group and aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup and a monovalent non-aromatic condensed heteropolycyclic group.

Hereinafter, a compound and an organic light-emitting device accordingto embodiments are described in detail with reference to SynthesisExample and Examples. However, the organic light-emitting device is notlimited thereto. The wording “B was used instead of A” used indescribing Synthesis Examples means that a molar equivalent of A wasidentical to a molar equivalent of B.

EXAMPLES Synthesis Example 1 Synthesis of Compound 6 Synthesis ofCompound A3

2,5-dibromo-4-methylpyridine (10 grams (g), 39.86 millimoles (mmol)),phenylbornic acid (5.35 g, 43.85 mmol), Pd(OAc)₂ (0.90 g, 3.99 mmol),PPh₃ (2.09 g, 7.97 mmol), and K₂CO₃ (11.02 g, 79.72 mmol) were mixedwith 100 mL of acetonitrile and 50 milliliters (mL) of methanol, andthen, the mixture was stirred at a temperature of 50° C. for 18 hoursand cooled to room temperature and filtered. Methylenechloride (“MC”)was used to separate an organic layer from the result, and an anhydrousmagnesium sulfate (MgSO₄) was added thereto to perform dehydration andthen, the result was filtered. A solvent in the obtained filtrate wasremoved under reduced pressure and the obtained residual was refined bycolumn chromatography using ethylacetate (“EA”) and hexane at a ratio of3:97 to obtain 6 g (61%) of Compound A3.

Synthesis of Compound A2

100 mL of tetrahydrofuran (“THF”) was added to Compound A3 (6 g, 24.18mmol), and then, the mixture was cooled to a temperature of −78° C. andn-BuLi (16.6 mL, 26.60 mmol) was slowly added thereto, and the resultwas stirred at a temperature of −78° C. for 1 hour. Then, TMSCI (3.38mL, 26.60 mmol) was added thereto, and a reaction was carried out at atemperature of −78° C. for 1 hour, and then, the temperature was raisedto room temperature and the reaction was carried out for 12 hours. Anorganic layer separated therefrom was extracted using MC, and ananhydrous magnesium sulfate was added thereto to perform dehydration.The result was filtered and a solvent in the obtained filtrate wasremoved under reduced pressure. The residual was purified by columnchromatography using EA (ethyl acetate) and hexane at a ratio of 4:96 toobtain 4.5 g (77%) of Compound A2.

Synthesis of Compound A1

Compound A2 (4.27 g, 17.68 mmol) was mixed with 100 mL of THF, and thenthe result was cooled to a temperature of −78° C. and lithiumdiisopropylamide (LDA, 16 mL, 31.83 mmol) was slowly added thereto.Next, the result was stirred at a temperature of −78° C. for 1 hour toperform a reaction, and then, the temperature was raised to roomtemperature and then, the reaction was further carried out for 1.5hours. Then, the temperature was dropped to a temperature of −78° C.,and 2-bromopropane (2.99 mL, 31.83 mmol) was slowly added to the resultand the temperature was raised to room temperature and the reaction wascarried out for 12 hours. An organic layer separated therefrom wasextracted using MC, and an anhydrous magnesium sulfate was added theretoto perform dehydration. The result was filtered and a solvent in theobtained filtrate was removed under reduced pressure. The residual waspurified by column chromatography using EA and hexane at a ratio of 4:96to obtain 3.73 g (74%) of Compound A1.

Synthesis of Compound M2A

2-phenylpyridine (14.66 g, 94.44 mmol) and iridium chloride (14.8 g,41.97 mmol) were mixed with 210 mL of ethoxyethanol and 70 mL ofdistilled water, and then the mixture was stirred while refluxing for 24hours to carry out the reaction, and then, the temperature was droppedto room temperature. The resultant solid was separated by filtration,and then, sufficiently, sequentially washed with water, methanol, andhexane in this stated order. The obtained solid was dried in a vacuumoven to obtain 20.2 g (90%) of Compound M2A.

Synthesis of Compound M1A

Compound M2A (4.5 g, 4.20 mmol) was mixed with 60 mL of MC, and then,AgOTf (2.16 g, 8.41 mmol) dissolved in 20 mL of methanol was addedthereto. Next, while being blocked from light by using an aluminum foil,the mixture was stirred at room temperature for 18 hours to carry outthe reaction, and the generated solid was removed by celite filtration,and a solvent in the obtained filtrate was removed under reducedpressure. The obtained solid (Compound M1) was used for the subsequentreaction without purification.

Synthesis of Compound 6

Compound M1A (5 g, 7 mmol) and Compound A1 (2.98 g, 10.50 mmol) weremixed with 90 mL of ethanol, and the result was stirred while refluxingfor 18 hours to carry out the reaction, and then, the temperature wasdropped. The resultant mixture was filtered to separate a solid, whichwas then sufficiently washed with ethanol and hexane, and then, columnchromatography was performed thereon using MC and hexane at a ratio of35:65 to obtain 2.1 g (38%) of Compound 6. The obtained product wasconfirmed by Mass and HPLC analysis.

HRMS(MALDI) calculated for C₄₀H₄₀IrN₃Si: m/z 783.2621. Found: 783.2625.

Synthesis Example 2 Synthesis of Compound 96 Synthesis of Compound B3

10.4 g (80%) of Compound B3 was prepared in the same manner as used tosynthesize Compound A3 in Synthesis Example 1, except that[1,1′-biphenyl]-3-ylboronic acid (8.68 g, 43.85 mmol) was used insteadof phenylbornic acid, and acetonitrile and methanol were respectivelyused in amounts of 120 mL and 60 mL.

Synthesis of Compound B2

4.6 g (78%) of Compound B2 was prepared in the same manner as used tosynthesize Compound A2 in Synthesis Example 1, except that Compound B3(6 g, 18.51 mmol) was used instead of Compound A3 and n-BuLi was used inan amount of 12.8 mL (20.36 mmol).

Synthesis of Compound B1

3.9 g (86%) of Compound B1 was prepared in the same manner as used tosynthesize Compound A1 in Synthesis Example 1, except that Compound B2(4 g, 12.60 mmol) was used instead of Compound A2 and LDA was used in anamount of 11.34 mL (22.68 mmol).

Synthesis of Compound 96

1.5 g (30%) of Compound 96 was prepared in the same manner as used tosynthesize Compound 6 in Synthesis Example 1, except that Compound M1A(4.2 g, 5.89 mmol) and Compound B1 (3.18 g, 8.83 mmol) were used insteadof Compound M1A (5 g, 7 mmol) and Compound A1 (2.98 g, 10.50 mmol),respectively. The obtained product was confirmed by Mass and HPLCanalysis.

HRMS(MALDI) calculated for C₄₆H₄₄IrN₃Si: m/z 859.2934. Found: 859.2930.

Synthesis Example 3 Synthesis of Compound 136

1.4 g (31%) of Compound 136 was prepared in the same manner as used tosynthesize Compound 6 in Synthesis Example 1, except that Compound M1A(4 g, 5.60 mmol), Compound C1 (2.55 g, 8.41 mmol), and 60 mL of ethanolwere used instead of Compound M1A (5 g, 7 mmol), Compound A1, and 90 mLof ethanol, respectively. The obtained product was confirmed by Mass andHPLC analysis.

HRMS(MALDI) calculated for C₄₂H₃₆IrN₃Si: m/z 803.2308. Found: 803.2313.

Synthesis Example 4 Synthesis of Compound 189 Synthesis of Compound M2B

14.0 g (88%) of Compound M2B was prepared in the same manner as used tosynthesize Compound M2A in Synthesis Example 1, except that2-phenyl(d5)-pyridine (10.64 g, 66.41 mmol) and iridium chloride (10.41g, 29.52 mmol) were respectively used instead of 2-phenylpyridine (14.66g, 94.44 mmol) and iridium chloride (14.8 g, 41.97 mmol), andethoxyethanol and distilled water were used in amounts of 180 mL and 70mL.

Synthesis of Compound M1B

Compound M1B was prepared in the same manner as used to synthesizeCompound M1A in Synthesis Example 1, except that Compound M2B (4.52 g,4.17 mmol) was used instead of Compound M2A. Compound M1B was used forthe subsequent process without purification.

Synthesis of Compound 189

2.7 g (41%) of Compound 189 was prepared in the same manner as used tosynthesize Compound 6 in Synthesis Example 1, except that Compound M1B(6 g, 8.34 mmol), Compound A1 (3.55 g, 12.51 mmol) and 60 mL of ethanolwere used instead of Compound M1A, Compound A1 (2.98 g, 10.50 mmol) and90 mL of ethanol, respectively. The obtained product was confirmed byMass and HPLC analysis.

HRMS(MALDI) calculated for C₄₀H₃₄D₆IrN₃Si: m/z 789.2997. Found:789.2990.

Synthesis Example 5 Synthesis of Compound 209 Synthesis of Compound D4

100 mL of THF was added to bromobenzene (d5) (10.72 g, 66.48 mmol), andthen, the temperature was dropped to a temperature of −78° C., and then,n-BuLl (49.86 mL, 79.77 mmol) was slowly added thereto. Next, while thetemperature was maintained at −78° C., the reaction was carried out for30 minutes, and then,2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (16.27 mL, 79.77mmol) was added thereto, and the temperature was raised to roomtemperature to carry out the reaction, and the result was stirred for 18hours to carry out the reaction at room temperature. From the obtainedmixture, an organic layer was extracted using EA, and anhydrousmagnesium sulfate (MgSO4) was added thereto to perform dehydration. Theresult was filtered and a solvent in the obtained filtrate was removedunder reduced pressure, and the residual was subjected to columnchromatography using ethylacetate (EA) and hexane at a ratio of 4:96 to11.7 g (84%) of obtain Compound D4.

Synthesis of Compound D3

2,5-dibromo-4-methylpyridine (11.89 g, 47.40 mmol), Compound D4 (10.90g, 52.14 mmol), Pd(OAc)₂ (1.06 g, 4.74 mmol), PPh₃ (2.49 g, 9.48 mmol),and KOH (5.32 g, 94.81 mmol) were mixed with 180 mL of acetonitrile, andthen, at a temperature of 50° C., the mixture was stirred for 18 hours,and cooled to room temperature and filtered. From the result, an organiclayer was extracted using methylenechloride (“MC”), and an anhydrousmagnesium sulfate (MgSO₄) was added thereto to perform dehydration, andthen, the result was filtered, and a solvent in the obtained filtratewas removed under reduced pressure. The residual was purified by columnchromatography using ethylacetate (“EA”) and hexane at a ratio of 3:97to obtain 9.7 g (81%) of Compound D3.

Synthesis of Compound D2

6.4 g (73%) of Compound D2 was prepared in the same manner as used tosynthesize Compound A2 in Synthesis Example 1, except that Compound D3(9 g, 35.55 mmol) was used instead of Compound A3 and THF was used in anamount of 120 mL and n-BuLi was used in an amount of 24.5 mL (39.11mmol).

Synthesis of Compound D1

3.3 g (70%) of Compound D1 was prepared in the same manner as used tosynthesize Compound A1 in Synthesis Example 1, except that Compound D2(4 g, 16.23 mmol) was used instead of Compound A2 and THF was used in anamount of 70 mL and LDA was used in an amount of 14.61 mL (29.22 mmol).

Synthesis of Compound 209

1.7 g (39%) of Compound 209 was prepared in the same manner as used tosynthesize Compound 6 in Synthesis Example 1, except that Compound M1A(4 g, 5.61 mmol), Compound D1 (2.43 g, 8.40 mmol), and 60 mL of ethanolwere used instead of Compound M1A (5 g, 7 mmol), Compound A1 (2.98 g,10.50 mmol), and 90 mL of ethanol, respectively. The obtained productwas confirmed by Mass and HPLC analysis.

HRMS(MALDI) calculated for C₄₀H₃₆D₄IrN₃Si: m/z 787.2872. Found:787.2879.

Synthesis Example 6 Synthesis of Compound 241 Synthesis of Compound M2C

9.9 g (77%) of Compound M2C was prepared in the same manner as used tosynthesize Compound M2A in Synthesis Example 1, except that2-methyl(d3)-6-phenylpyridine(2-methyl(d3)-6-phenylpyridine) (8.792 g,51.05 mmol), iridium chloride (8 g, 22.69 mmol), 150 mL ofethoxyethanol, and 50 mL of distilled water were used instead of2-phenylpyridine, iridium chloride (14.8 g, 41.97 mmol), 210 mL ofethoxyethanol, and 70 mL of distilled water, respectively.

Synthesis of Compound M1C

Compound M1C was prepared in the same manner as used to synthesizeCompound M1A in Synthesis Example 1, except that Compound M2C (4.57 g,4.01 mmol) was used instead of Compound M2A. Compound M1C was used forthe subsequent process without purification.

Synthesis of Compound 241

1.3 g (20%) of Compound 241 was prepared in the same manner as used tosynthesize Compound 6 in Synthesis Example 1, except that Compound M1C(6 g, 8.02 mmol), Compound A1 (3.41 g, 12.03 mmol), and 60 mL of ethanolwere used instead of Compound M1A (5 g, 7 mmol), Compound A1 (2.98 g,10.50 mmol), and 90 mL of ethanol, respectively. The obtained productwas confirmed by Mass and HPLC analysis.

HRMS(MALDI) calculated for C₄₂H₃₈D₆IrN₃Si: m/z 817.3310. Found:817.3301.

Synthesis Example 7 Synthesis of Compound 296 Synthesis of Compound M2D

7.4 g (62%) of Compound M2D was prepared in the same manner as used tosynthesize Compound M2A in Synthesis Example 1, except that Compound A1(9.66 g, 34.06 mmol), iridium chloride (5.34 g, 15.14 mmol), 150 mL ofethoxyethanol, and 50 mL of distilled water were used instead of2-phenylpyridine, iridium chloride (14.8 g, 41.97 mmol), 210 mL ofethoxyethanol, and 70 mL of distilled water, respectively.

Synthesis of Compound M1D

Compound M1D was prepared in the same manner as used to synthesizeCompound M1A in Synthesis Example 1, except that Compound M2D (4.90 g,3.09 mmol) and AgOTf (1.59 g, 6.18 mmol) were used instead of CompoundM2A and AgOTf (2.16 g, 8.41 mmol), respectively. Compound M1D was usedfor the subsequent reaction without purification.

Synthesis of Compound 296

2.0 g (35%) of Compound 296 was prepared in the same manner as used tosynthesize Compound 6 in Synthesis Example 1, except that Compound M1D(6 g, 6.18 mmol) and phenylpyridine (1.44 g, 9.28 mmol) were usedinstead of Compound M1A (5 g, 7 mmol) and Compound A1 (2.98 g, 10.50mmol), respectively. The obtained product was confirmed by Mass and HPLCanalysis.

HRMS(MALDI) calculated for C₄₇H₅₆IrN₃Si₂: m/z 911.3642. Found: 911.3648.

Comparative Synthesis Example 1 Synthesis of Comparative Compound 1

2.4 g (39%) of Comparative Compound 1 was prepared in the same manner asused to synthesize Compound 6 in Synthesis Example 1, except thatCompound M1A (6 g, 8.41 mmol) and Compound A2 (3.0 g, 12.61 mmol) wereused instead of Compound M1A (5 g, 7 mmol) and Compound A1 (2.98 g,10.50 mmol), respectively. The obtained product was confirmed by Massand HPLC analysis.

HRMS(MALDI) calculated for C₃₇H₃₄IrN₃Si: m/z 741.2151. Found: 741.2157.

Example 1

An ITO glass substrate was cut to a size of 50 mm×50 mm×0.5 mm and then,sonicated in acetone isopropyl alcohol and pure water, each for 15minutes, and then, washed by exposure to UV ozone for 30 minutes.

Then, m-MTDATA was deposited on an ITO electrode (anode) of the glasssubstrate at a deposition speed of 1 Å/sec to form a hole injectionlayer having a thickness of 600 Å, and then, α-NPD was deposited on thehole injection layer at a deposition speed of 1 Å/sec to form a holetransport layer having a thickness of 250 Å.

Compound 6 (dopant) and CBP (host) were co-deposited on the holetransport layer at a deposition speed 0.1 Å/sec and a deposition speedof 1 Å/sec, respectively, to form an emission layer having a thicknessof 400 Å.

BAlq was deposited on the emission layer at a deposition speed of 1Å/sec to form a hole blocking layer having a thickness of 50 Å, and Alq₃was deposited on the hole blocking layer to form an electron transportlayer having a thickness of 300 Å, and then, LiF was deposited on theelectron transport layer to form an electron injection layer having athickness of 10 Å, and then, Al was vacuum deposited on the electroninjection layer to form a second electrode (cathode) having a thicknessof 1200 Å, thereby completing manufacturing of an organic light-emittingdevice having a structure of ITO/m-MTDATA (600 Å)/α-NPD (250 Å)/CBP+10%(Compound 6) (400 Å)/Balq (50 Å)/Alq3 (300 Å)/LiF (10 Å)/Al (1200 Å).

Examples 2 to 7 and Comparative Examples 1 and 2

Organic light-emitting devices were manufactured in the same manner asin Example 1, except that in forming an emission layer, for use as adopant, corresponding compounds shown in Table 2 were used instead ofCompound 6.

Evaluation Example 1 Evaluation on Characteristics of OrganicLight-Emitting Devices

The organic light-emitting devices manufactured according to Examples 1to 7 and Comparative Examples 1 and 2 were evaluated in terms of drivingvoltage, efficiency, power, color purity, quantum efficiency, andlifespan (T₉₅). Results thereof are shown in Table 2. This evaluationwas performed using a current-voltage meter (Keithley 2400) and abrightness meter (Minolta Cs-1000A), and the lifespan (T95)(at 6000 nit)was evaluated by measuring a time taken until brightness was reduced to95% of the initial brightness of 100%.

TABLE 2 Driving Voltage Efficiency Power Quantum Lifespan Dopant Voltage(V) (cd/A) (lm/W) CIEx CIEy Efficiency (%) (hr), (T95) Ex 1 Compound 65.0 49.2 30.9 0.340 0.605 19 250 Ex 2 Compound 96 4.9 48.7 31.2 0.3420.604 19 234 Ex 3 Compound 136 5.2 52.2 31.5 0.349 0.605 19 190 Ex 4Compound 189 5.0 49.9 31.3 0.340 0.604 19 285 Ex 5 Compound 209 5.0 49.331.0 0.340 0.605 19 270 Ex 6 Compound 241 4.9 53.1 34.0 0.338 0.605 19270 Ex 7 Compound 296 5.1 52.4 32.3 0.344 0.604 19 260 CEx 1 Comparative5.3 48.5 28.7 0.344 0.604 18 135 Compound 1 CEx 2 Ir(ppy)₃ 6.5 40.2 19.40.330 0.604 18 15 Ex = Example; CEx = Comparative Example

From Table 2, it was confirmed that the organic light-emitting devicesof Examples 1 to 7 had a lower driving voltage, higher efficiency,higher power, higher color purity, higher quantum efficiency, and longerlifetime than the organic light-emitting devices of Comparative Examples1 and 2.

The organometallic compound according to embodiments has excellentelectric characteristics and thermal stability. Accordingly, an organiclight-emitting device including the organometallic compound may have lowdriving voltage, high efficiency, high power, high quantum efficiency,long lifespan, and excellent color purity.

1. An organometallic compound represented by Formula 1:M(L₁)_(n1)(L₂)_(n2),  Formula 1 wherein M is iridium (Ir) or platinum(Pt), wherein L₁ is a ligand selected from substituted and unsubstitutedphenylpyridine that coordinates to M via a carbon atom of the phenylring and the nitrogen atom of the pyridine ring and L₂ is a ligandrepresented by Formula 2B, and wherein L₁ and L₂ in Formula 1 aredifferent from each other,

wherein, CY₃ is a benzene, R₁ to R₃ in Formula 2B are each independentlyselected from a C₁-C₁₀ alkyl group; and a C₁-C₁₀ alkyl group, which issubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,and a C₁-C₁₀ alkyl group, any substituent on L₁, and R₁₁ to R₁₄ inFormula 2B, are each independently selected from a hydrogen, adeuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ aryloxygroup, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group having8 to 60 carbon atoms, a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group having 1 to 60 carbonatoms, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and —P(═O)(Q₈)(Q₉),wherein R₁₂ in Formula 2B is not a hydrogen, a —CH₃, a cyano group; andi) two substituents on the pyridine ring of the L₁, together with thepyridine ring, optionally form a 5,6,7,8-tetrahydroisoquinoline, and ii)two substituents on the phenyl ring of the L₁, together with the phenylring, optionally form a dibenzofuran, a dibenzothiophene or a carbazole,and b1 in Formula 2B is selected from 1, 2, 3, and 4, and wherein inFormula 1, n1 and n2 are each independently 1 or 2, with the provisothat a sum of n1 and n2 is 2 when M is Pt, or 3 when M is Ir, wherein *and *′ in Formula 2B are each a binding site to M in Formula 1; andwherein at least one of substituents of the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryloxy group, thesubstituted C₆-C₆₀ arythio group, the substituted C₁-C₆₀ heteroarylgroup, the substituted monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms, and the substituted monovalentnon-aromatic condensed heteropolycyclic group having 1 to 60 carbonatoms is selected from: a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₁-C₁₀ cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₂-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), and—P(═O)(Q₁₈)(Q₁₉); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms, and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms; a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group having 8 to 60 carbonatoms, and a monovalent non-aromatic condensed heteropolycyclic grouphaving 1 to 60 carbon atoms, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkenyl group, aC₁-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), and—P(═O)(Q₂₈)(Q₂₉); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅) —B(Q₃₆)(Q₃₇), and—P(═O)(Q₃₈)(Q₃₉); wherein Q₁ to Q₉, Q₁₁ to Q₁₉, (Q₂₁) to Q₂₉, and Q₃₁ toQ₃₉ are each independently selected from a hydrogen, a deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryl group substituted with at least one selected from a C₁-C₆₀ alkylgroup and a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group having 8 to 60 carbon atoms and a monovalentnon-aromatic condensed heteropolycyclic group having 1 to 60 carbonatoms.
 2. (canceled)
 3. (canceled)
 4. The organometallic compound ofclaim 1, wherein R₁ to R₃ in Formula 2B are each independently selectedfrom a methyl group, an ethyl group, an n-propyl group, an isopropylgroup, an n-butyl group, an isobutyl group, a sec-butyl group, atert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentylgroup, a tert-pentyl group, an n-hexyl group, an isohexyl group, asec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptylgroup, a sec-heptyl group, a tert-heptyl group, an n-octyl group, anisooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group,an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decylgroup, an isodecyl group, a sec-decyl group, and a tert-decyl group,each of which is unsubstituted; and a methyl group, an ethyl group, ann-propyl group, an isopropyl group, an n-butyl group, an isobutyl group,a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a sec-pentyl group, a tert-pentyl group, an n-hexyl group, anisohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptylgroup, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, ann-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group,an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonylgroup, an n-decyl group, an isodecyl group, a sec-decyl group, and atert-decyl group, each of which is substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃,—CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, and a C₁-C₁₀ alkyl group.
 5. Theorganometallic compound of claim 1, wherein R₁ to R₃ in Formula 2B areeach independently selected from a methyl group, an ethyl group, ann-propyl group, an isopropyl group, an n-butyl group, an isobutyl group,a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a sec-pentyl group, and a tert-pentyl group, each of which isunsubstituted; and a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentylgroup, and a tert-pentyl group, each of which is substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, and a C₁-C₁₀ alkyl group.6. The organometallic compound of claim 1, wherein R₁ to R₃ in Formula2B are each independently selected from —CH₃, —CH₂CH₃, —CD₃, —CD₂H,—CDH₂, —CH₂CD₃, and —CD₂CH₃.
 7. The organometallic compound of claim 1,wherein R₁ to R₃ in Formula 2B are identical.
 8. The organometalliccompound of claim 1, wherein any substituent on L1, R₁₁, R₁₃, and R₁₄ inFormulas 2B are each independently selected from: a hydrogen, adeuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkylgroup, and a C₁-C₂₀ alkoxy group, each of which is unsubstituted; aC₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₁-C₁₄ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group having 8 to60 carbon atoms, and a monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms; a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₁-C₁₄ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, anda monovalent non-aromatic condensed heteropolycyclic group having 1 to60 carbon atoms, each of which is unsubstituted; a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₁-C₁₄ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, anda monovalent non-aromatic condensed heteropolycyclic group having 1 to60 carbon atoms, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₁-C₁₄heteroaryl group, a monovalent non-aromatic condensed polycyclic grouphaving 8 to 60 carbon atoms, and a monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms; i) two substituentson the pyridine ring of the L₁, together with the pyridine ring,optionally form a 5,6,7,8-tetrahydroisoquinoline and ii) twosubstituents on the phenyl ring of the L₁, together with the phenylring, optionally form a dibenzofuran, a dibenzothiophene or a carbazole;and —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and —P(═O)(Q₈)(Q₉), whereinQ₁ to Q₉ are each independently selected from a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₆-C₁₄ aryl groupsubstituted with at least one selected from a C₁-C₂₀ alkyl group and aC₆-C₁₄ aryl group, a C₁-C₁₄ heteroaryl group, a monovalent non-aromaticcondensed polycyclic group having 8 to 60 carbon atoms, and a monovalentnon-aromatic condensed heteropolycyclic group having 1 to 60 carbonatoms.
 9. The organometallic compound of claim 1, wherein anysubstituent on L₁, R₁₁, R₁₃, and R₁₄ in Formula 2B are eachindependently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, —SF₅, a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group; a C₁-C₂₀alkyl group and a C₁-C₂₀ alkoxy group, each substituted with at leastone selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂,—CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₁₀ alkyl group, a cyclopentylgroup, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group; a cyclopentyl group,a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a fluorenyl group, a pyrrolylgroup, a thiophenyl group, a furanyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, apyrimidinyl group, a pyridazinyl group, an isoindolyl group, an indolylgroup, an indazolyl group, a purinyl group, a quinolinyl group, anisoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, an imidazopyridinyl group, and an imidazopyrimidinyl group; acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornenyl group, a cyclopentenyl group,a cyclohexenyl group, a cycloheptenyl group, a fluorenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, an imidazopyridinyl group, and an imidazopyrimidinyl group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzooxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, and animidazopyrimidinyl group; and —B(Q₆)(Q₇) and —P(═O)(Q₈)(Q₉), wherein Q₆to Q₉ are each independently selected from a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a pyridinylgroup, a pyrimidinyl group, a triazinyl group, and a carbazolyl group;and a phenyl group and a naphthyl group, each substituted with at leastone selected from a C₁-C₂₀ alkyl group, a phenyl group, and a naphthylgroup.
 10. The organometallic compound of claim 1, wherein, anysubstituent on L₁, R₁₁, R₁₃, and R₁₄ in Formula 2B are eachindependently selected from: a hydrogen, a deuterium, —F, a cyano group,a nitro group, —SF₅, a methyl group, an ethyl group, an n-propyl group,an isopropyl group, an n-butyl group, an isobutyl group, a sec-butylgroup, a tert-butyl group, an n-pentyl group, an isopentyl group, asec-pentyl group, a tert-pentyl group, an n-hexyl group, an isohexylgroup, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, anisoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octylgroup, an isooctyl group, a sec-octyl group, a tert-octyl group, ann-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group,an n-decyl group, an isodecyl group, a sec-decyl group, a tert-decylgroup, a methoxy group, an ethoxy group, a propoxy group, a butoxygroup, a pentoxy group, a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a pyridinyl group, and a pyrimidinyl group; amethyl group, an ethyl group, an n-propyl group, an isopropyl group, ann-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group,an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentylgroup, an n-hexyl group, an isohexyl group, a sec-hexyl group, atert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptylgroup, a tert-heptyl group, an n-octyl group, an isooctyl group, asec-octyl group, a tert-octyl group, an n-nonyl group, an isononylgroup, a sec-nonyl group, a tert-nonyl group, an n-decyl group, anisodecyl group, a sec-decyl group, a tert-decyl group, a methoxy group,an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornenyl group, a cyclopentenyl group,a cyclohexenyl group, a cycloheptenyl group, a pyridinyl group, and apyrimidinyl group, each substituted with at least one selected from adeuterium, —F, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a cyano group, anitro group, a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a cyclopentylgroup, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group; and —B(Q₆)(Q₇) and—P(═O)(Q₈)(Q₉), wherein Q₆ to Q₉ are each independently selected from aC₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, and anaphthyl group; a phenyl group and a naphthyl group, each substitutedwith at least one selected from a C₁-C₁₀ alkyl group, a phenyl group,and a naphthyl group.
 11. The organometallic compound of claim 1,wherein R₁₂ in Formula 2B is selected from a C₂-C₂₀ alkyl group and aC₂-C₂₀ alkoxy group; a methyl group and a methoxy group, eachsubstituted with at least one selected from a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₁-C₁₄ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group having 8 to60 carbon atoms, and a monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms; a C₂-C₂₀ alkyl groupand a C₂-C₂₀ alkoxy group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄ arylgroup, a C₁-C₁₄ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group having 8 to 60 carbon atoms, and a monovalentnon-aromatic condensed heteropolycyclic group having 1 to 60 carbonatoms; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₁-C₁₄heteroaryl group, a monovalent non-aromatic condensed polycyclic grouphaving 8 to 60 carbon atoms, and a monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms; a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₁-C₁₄ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, anda monovalent non-aromatic condensed heteropolycyclic group having 1 to60 carbon atoms, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄ aryl group, a C₁-C₁₄heteroaryl group, a monovalent non-aromatic condensed polycyclic grouphaving 8 to 60 carbon atoms, and a monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms; and —N(Q₁)(Q₂),—Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and —P(═O)(Q₈)(Q₉), wherein Q₁ to Q₉ areeach independently selected from a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, aC₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₁₄aryl group, a C₆-C₁₄ aryl group substituted with at least one selectedfrom a C₁-C₂₀ alkyl group and a C₆-C₁₄ aryl group, a C₁-C₁₄ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group having 8 to60 carbon atoms, and a monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms.
 12. Theorganometallic compound of claim 1, wherein R₁₂ in Formula 2B isselected from a C₂-C₂₀ alkyl group and a C₂-C₂₀ alkoxy group; a methylgroup and a methoxy group, each substituted with at least one selectedfrom a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup; a C₂-C₂₀ alkyl group and a C₂-C₂₀ alkoxy group, each substitutedwith at least one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃,—CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₂-C₁₀ alkylgroup, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup; a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, afluorenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group,an imidazolyl group, a pyrazolyl group, a thiazolyl group, anisothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anisoindolyl group, an indolyl group, an indazolyl group, a purinyl group,a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzooxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, and animidazopyrimidinyl group; a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a fluorenyl group, a pyrrolyl group, a thiophenylgroup, a furanyl group, an imidazolyl group, a pyrazolyl group, athiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolylgroup, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, apyridazinyl group, an isoindolyl group, an indolyl group, an indazolylgroup, a purinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a carbazolyl group, a phenanthrolinyl group, abenzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group, each of which is substitutedwith at least one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃,—CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a fluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, an imidazopyridinyl group, and an imidazopyrimidinyl group; and—B(Q₆)(Q₇) and —P(═O)(Q₈)(Q₉), wherein Q₆ to Q₉ are each independentlyselected from a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a naphthyl group, a pyridinyl group, a pyrimidinyl group, atriazinyl group, and a carbazolyl group; and a phenyl group and anaphthyl group, each substituted with at least one selected from aC₁-C₂₀ alkyl group, a phenyl group, and a naphthyl group.
 13. Theorganometallic compound of claim 1, wherein R₁₂ in Formula 2B isselected from an ethyl group, an n-propyl group, an isopropyl group, ann-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group,an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentylgroup, an n-hexyl group, an isohexyl group, a sec-hexyl group, atert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptylgroup, a tert-heptyl group, an n-octyl group, an isooctyl group, asec-octyl group, a tert-octyl group, an n-nonyl group, an isononylgroup, a sec-nonyl group, a tert-nonyl group, an n-decyl group, anisodecyl group, a sec-decyl group, a tert-decyl group, an ethoxy group,a propoxy group, a butoxy group, a pentoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a pyridinyl group, and apyrimidinyl group; a methyl group and a methoxy group, each substitutedwith at least one selected from a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group; and an ethyl group, an n-propyl group,an isopropyl group, an n-butyl group, an isobutyl group, a sec-butylgroup, a tert-butyl group, an n-pentyl group, an isopentyl group, asec-pentyl group, a tert-pentyl group, an n-hexyl group, an isohexylgroup, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, anisoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octylgroup, an isooctyl group, a sec-octyl group, a tert-octyl group, ann-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonyl group,an n-decyl group, an isodecyl group, a sec-decyl group, a tert-decylgroup, an ethoxy group, a propoxy group, a butoxy group, a pentoxygroup, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, apyridinyl group, and a pyrimidinyl group, each of which is substitutedwith at least one selected from a deuterium, —F, —CD₃, —CD₂H, —CDH₂,—CF₃, —CF₂H, —CFH₂, a cyano group, a nitro group, a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group.
 14. The organometallic compound of claim1, wherein any substituent on L₁, R₁₁, R₁₃, and R₁₄ in Formula 2B areeach independently selected from a hydrogen, a deuterium, —F, a cyanogroup, a nitro group, —SF₅, —CH₃, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a group represented by Formulas 9-1 to 9-17, and a grouprepresented by Formulas 10-7 to 10-16, and R₁₂ in Formula 2B is selectedfrom the group represented by Formulas 9-1 to 9-17 and groupsrepresented by Formulas 10-7 to 10-16:


15. The organometallic compound of claim 1, wherein L₁ is a ligandrepresented by Formulas 2-1 or 2-112:

wherein Z₁, and Z₂, in Formulas 2-1 and 2-112 are each independentlyselected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, —SF₅, ahydroxyl group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group having 8 to 60 carbon atoms, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic grouphaving 1 to 60 carbon atoms, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇),and —P(═O)(Q₈)(Q₉), wherein Q₁ to Q₉ are each independently selectedfrom a hydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from a C₁-C₆₀ alkyl group and aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms, aa4 andab4 are each independently selected from, 1, 2, 3, and 4, and * and *′indicate binding sites to M, and wherein at least one of thesubstituents of the substituted C₁-C₆₀ alkyl group, the substitutedC₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group, thesubstituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arythio group, the substituted C₁-C₆₀ heteroaryl group, the substituteda monovalent non-aromatic condensed polycyclic group having 8 to 60carbon atoms, and the substituted monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms is selected from: adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenylgroup, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, eachsubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₁-C₁₀cycloalkenyl group, a C₂-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₂-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic grouphaving 8 to 60 carbon atoms, a monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms, —N(Q₁)(Q₁₂),—Si(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), and —P(═O)(Q₁₈)(Q₁₉); a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group having 8 to 60 carbonatoms, and a monovalent non-aromatic condensed heteropolycyclic grouphaving 1 to 60 carbon atoms; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, anda monovalent non-aromatic condensed heteropolycyclic group having 1 to60 carbon atoms, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkenyl group, a C₁-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), and—P(═O)(Q₂₈)(Q₂₉); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅) —B(Q₃₆)(Q₃₇), and—P(═O)(Q₃₈)(Q₃₉); wherein Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ to Q₃₉ areeach independently selected from a hydrogen, a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from a C₁-C₆₀ alkyl group and aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms. 16.(canceled)
 17. The organometallic compound of claim 1, wherein L₁ inFormula 1 is selected from ligands represented by Formulas 2-1(1) to2-1(18):

wherein in Formulas 2-1(1) to 2-1(18), Z₁, Z_(1a), Z_(1b), Z_(1c),Z_(1d), Z₂, Z_(2a), Z_(2b), Z_(2c), and Z_(2d) are each independentlyselected from, a deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group having 8 to 60 carbonatoms, a substituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms, —N(Q₁)(Q₂),—Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and —P(═O)(Q₈)(Q₉), wherein Q₁ to Q₉ areeach independently selected from a hydrogen, a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from a C₁-C₆₀ alkyl group and aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms, whereinnone of Z₁, Z₂, Z_(1a), Z_(1b), Z_(1c), Z_(1a), Z_(2a), Z_(2b), Z_(2c),and Z_(2d) are hydrogen, * and *′ indicate binding sites to M, andwherein at least one of the substituents of the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryloxy group, thesubstituted C₆-C₆₀ arythio group, the substituted C₁-C₆₀ heteroarylgroup, the substituted a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms, and the substituted monovalentnon-aromatic condensed heteropolycyclic group having 1 to 60 carbonatoms is selected from: a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group;a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₁-C₁₀ cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₂-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), and—P(═O)(Q₁₈)(Q₁₉); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms, and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms; a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group having 8 to 60 carbonatoms, and a monovalent non-aromatic condensed heteropolycyclic grouphaving 1 to 60 carbon atoms, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkenyl group, aC₁-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), and—P(═O)(Q₂₈)(Q₂₉); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅) —B(Q₃₆)(Q₃₇), and—P(═O)(Q₃₈)(Q₃₉); wherein Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ to Q₃₉ areeach independently selected from a hydrogen, a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from a C₁-C₆₀ alkyl group and aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms.
 18. Theorganometallic compound of claim 17, wherein Z₁, Z₂, Z_(1a), Z_(1b),Z_(1c), Z_(1d), Z_(2a), Z_(2b), Z_(2c), and Z_(2d) in Formulas 2-1(1) to2-1(8) are each independently selected from a deuterium, —F, a cyanogroup, a nitro group, —SF₅, a methyl group, an ethyl group, an n-propylgroup, an isopropyl group, an n-butyl group, an isobutyl group, asec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a sec-pentyl group, a tert-pentyl group, an n-hexyl group, anisohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptylgroup, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, ann-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group,an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonylgroup, an n-decyl group, an isodecyl group, a sec-decyl group, atert-decyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, and a pentoxy group; a methyl group, an ethyl group, ann-propyl group, an isopropyl group, an n-butyl group, an isobutyl group,a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a sec-pentyl group, a tert-pentyl group, an n-hexyl group, anisohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptylgroup, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, ann-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group,an n-nonyl group, an isononyl group, a sec-nonyl group, a tert-nonylgroup, an n-decyl group, an isodecyl group, a sec-decyl group, atert-decyl group, a methoxy group, an ethoxy group, a propoxy group, abutoxy group, and a pentoxy group, each substituted with at least oneselected from a deuterium, —F, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, acyano group, a nitro group, and a C₁-C₁₀ alkyl group; and a grouprepresented by one of Formulas 10-7 to 10-16:


19. The organometallic compound of claim 1, wherein L₂ is selected fromligands represented by Formulas 2B-1 to 2B-7, 2B-11 and 2B-12:

wherein Formulas 2B-1 to 2B-7, 2B-11 and 2B-12, R₁ to R₃ are eachindependently selected from a methyl group, an ethyl group, an n-propylgroup, an isopropyl group, an n-butyl group, an isobutyl group, asec-butyl group, a tert-butyl group, an n-pentyl group, an isopentylgroup, a sec-pentyl group, and a tert-pentyl group, each of which isunsubstituted; and a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentylgroup, and a tert-pentyl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃,—CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, and a C₁-C₁₀ alkyl group, R₁₁ and R₁₃to R₁₇ are each independently a deuterium, —F, a cyano group, a nitrogroup, —SF₅, a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentylgroup, a tert-pentyl group, an n-hexyl group, an isohexyl group, asec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptylgroup, a sec-heptyl group, a tert-heptyl group, an n-octyl group, anisooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group,an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decylgroup, an isodecyl group, a sec-decyl group, a tert-decyl group, amethoxy group, an ethoxy group, a propoxy group, a butoxy group, apentoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptylgroup, a cyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, apyridinyl group, and a pyrimidinyl group, each of which isunsubstituted; a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentylgroup, a tert-pentyl group, an n-hexyl group, an isohexyl group, asec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptylgroup, a sec-heptyl group, a tert-heptyl group, an n-octyl group, anisooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group,an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decylgroup, an isodecyl group, a sec-decyl group, a tert-decyl group, amethoxy group, an ethoxy group, a propoxy group, a butoxy group, apentoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptylgroup, a cyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, apyridinyl group, and a pyrimidinyl group, each substituted with at leastone selected from a deuterium, —F, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a cyano group, a nitro group, a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptylgroup, a cyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup; and —B(Q₆)(Q₇) and —P(═O)(Q₈)(Q₉), wherein Q₆ to Q₉ are eachindependently selected from a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group,a phenyl group, and a naphthyl group; and a phenyl group and a naphthylgroup, each substituted with at least one selected from a C₁-C₁₀ alkylgroup, a phenyl group, and a naphthyl group, and wherein R₁₂ is selectedfrom an ethyl group, an n-propyl group, an isopropyl group, an n-butylgroup, an isobutyl group, a sec-butyl group, a tert-butyl group, ann-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentylgroup, an n-hexyl group, an isohexyl group, a sec-hexyl group, atert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptylgroup, a tert-heptyl group, an n-octyl group, an isooctyl group, asec-octyl group, a tert-octyl group, an n-nonyl group, an isononylgroup, a sec-nonyl group, a tert-nonyl group, an n-decyl group, anisodecyl group, a sec-decyl group, a tert-decyl group, an ethoxy group,a propoxy group, a butoxy group, a pentoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a pyridinyl group, and apyrimidinyl group, each of which is unsubstituted; a methyl group and amethoxy group, each substituted with at least one selected from acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornenyl group, a cyclopentenyl group,a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group; and an ethyl group,an n-propyl group, an isopropyl group, an n-butyl group, an isobutylgroup, a sec-butyl group, a tert-butyl group, an n-pentyl group, anisopentyl group, a sec-pentyl group, a tert-pentyl group, an n-hexylgroup, an isohexyl group, a sec-hexyl group, a tert-hexyl group, ann-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, a tert-decyl group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a pyridinyl group, and a pyrimidinyl group, eachsubstituted with at least one selected from a deuterium, —F, —CD₃,—CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a cyano group, a nitro group, a C₁-C₁₀alkyl group, a C₁-C₁₀alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group.
 20. The organometallic compound of claim1, wherein n2 in Formula 1 is
 1. 21. The organometallic compound ofclaim 1, wherein in Formula 1, M is Ir and the sum of n1 and n2 is 3; orM is Pt and the sum of n1 and n2 is 2, and the organometallic compoundis neutral.
 22. The organometallic compound of claim 1, wherein theorganometallic compound is one of Compounds 1 to 75, 121 to 135, 154 to223, 234 to 307 and 323 to 388:


23. An organic light-emitting device comprising: a first electrode; asecond electrode; and an organic layer that is disposed between thefirst electrode and the second electrode and which comprises an emissionlayer, wherein the organic layer comprises the organometallic compoundof claim
 1. 24. The organic light-emitting device of claim 23, whereinthe first electrode is an anode, and the second electrode is a cathode,the organic layer comprises a hole transport region that is disposedbetween the first electrode and the emission layer and comprises atleast one of a hole injection layer, a hole transport layer, and anelectron blocking layer, and an electron transport region that isdisposed between the emission layer and the second electrode andcomprises at least one selected from a hole blocking layer, an electrontransport layer, and an electron injection layer.
 25. The organiclight-emitting device of claim 23, wherein the organometallic compoundis comprised in the emission layer, and wherein the emission layerfurther comprises a host, and an amount of the organometallic compoundis less than an amount of the host.
 26. A method of manufacturing anorganic light-emitting device, the method comprising: providing a firstelectrode; a second electrode; and an organic layer that is disposedbetween the first electrode and the second electrode and which comprisesan emission layer, wherein the emission layer comprises theorganometallic compound of claim
 1. 27. An organometallic compoundrepresented by Formula 1:M(L₁)_(n1)(L₂)_(n2),  Formula 1 wherein M is iridium (Ir), or platinum(Pt), wherein L₁ is a ligand selected from substituted and unsubstitutedphenylpyridine that coordinates to M via a carbon atom of the phenylring and the nitrogen atom of the pyridine ring and L₂ is a ligandrepresented by Formula 2B, and wherein L₁ and L₂ in Formula 1 aredifferent from each other,

wherein CY₃ is selected from a carbazole, a dibenzofuran and adibenzothiophene, R₁ to R₃ in Formula 2B are each independently selectedfrom a C₁-C₁₀ alkyl group; and a C₁-C₁₀ alkyl group, which issubstituted with at least one selected from a deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,and a C₁-C₁₀ alkyl group, any substituent on L₁, and R₁₁ to R₁₄ inFormulas 2B are each independently selected from a hydrogen, adeuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group having 8 to 60 carbonatoms, a substituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms, —N(Q₁)(Q₂),—Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and —P(═O)(Q₈)(Q₉), wherein R₁₂ in Formula2B is not a hydrogen, a —CH₃, or a cyano group; and i) two substituentson the pyridine ring of the L₁, together with the pyridine ring,optionally form a 5,6,7,8-tetrahydroisoquinoline and ii) twosubstituents on the phenyl ring of the L₁, together with the phenylring, optionally form a dibenzofuran, a dibenzothiophene or a carbazole,and b1 in Formula 2B is selected from 1, 2, 3, and 4, and wherein inFormula 1, n1 and n2 are each independently 1 or 2, with the provisothat a sum of n1 and n2 is 2 when M is Pt, or 3 when M is Ir, wherein *and *′ in Formula 2B are each a binding site to M in Formula 1; andwherein at least one of substituents of the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arythio group,the substituted C₁-C₆₀ heteroaryl group, the substituted a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, andthe substituted monovalent non-aromatic condensed heteropolycyclic grouphaving 1 to 60 carbon atoms is selected from: a deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, anda C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted withat least one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₁-C₁₀ cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₂-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), and—P(═O)(Q₁₈)(Q₁₉); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms, and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms; a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group having 8 to 60 carbonatoms, and a monovalent non-aromatic condensed heteropolycyclic grouphaving 1 to 60 carbon atoms, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkenyl group, aC₁-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), and—P(═O)(Q₂₈)(Q₂₉); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅) —B(Q₃₆)(Q₃₇), and—P(═O)(Q₃₈)(Q₃₉); wherein Q₁ to Q₉, Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ toQ₃₉ are each independently selected from a hydrogen, a deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryl group substituted with at least one selected from a C₁-C₆₀ alkylgroup and a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a C₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensedpolycyclic group having 8 to 60 carbon atoms and a monovalentnon-aromatic condensed heteropolycyclic group having 1 to 60 carbonatoms.
 28. The organometallic compound of claim 27, wherein R₁ to R₃ inFormula 2B are each independently selected from a methyl group, an ethylgroup, an n-propyl group, an isopropyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, and a tert-decyl group, each of which is unsubstituted;and a methyl group, an ethyl group, an n-propyl group, an isopropylgroup, an n-butyl group, an isobutyl group, a sec-butyl group, atert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentylgroup, a tert-pentyl group, an n-hexyl group, an isohexyl group, asec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptylgroup, a sec-heptyl group, a tert-heptyl group, an n-octyl group, anisooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group,an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decylgroup, an isodecyl group, a sec-decyl group, and a tert-decyl group,each of which is substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, and a C₁-C₁₀ alkyl group.
 29. The organometallic compound ofclaim 27, wherein any substituent on L₁, R₁₁, R₁₃, and R₁₄ in Formula 2Bare each independently selected from a hydrogen, a deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, —SF₅, a C₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxygroup; a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substitutedwith at least one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃,—CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a C₁-C₁₀ alkylgroup, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup; a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group; a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzooxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, and animidazopyrimidinyl group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornenyl group, a cyclopentenyl group,a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzooxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, and animidazopyrimidinyl group; and —B(Q₆)(Q₇) and —P(═O)(Q₈)(Q₉), wherein Q₆to Q₉ are each independently selected from a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a naphthyl group, a pyridinylgroup, a pyrimidinyl group, a triazinyl group, and a carbazolyl group;and a phenyl group and a naphthyl group, each substituted with at leastone selected from a C₁-C₂₀ alkyl group, a phenyl group, and a naphthylgroup.
 30. The organometallic compound of claim 27, wherein R₁₂ inFormula 2B is selected from a C₂-C₂₀ alkyl group and a C₂-C₂₀ alkoxygroup; a methyl group and a methoxy group, each substituted with atleast one selected from a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group; a C₂-C₂₀ alkyl group and a C₂-C₂₀ alkoxygroup, each substituted with at least one selected from a deuterium, —F,—Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group,a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₂-C₁₀ alkyl group, a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group; a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a fluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a carbazolyl group, aphenanthrolinyl group, a benzoimidazolyl group, a benzofuranyl group, abenzothiophenyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzooxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a dibenzofuranyl group, adibenzothiophenyl group, a benzocarbazolyl group, a dibenzocarbazolylgroup, an imidazopyridinyl group, and an imidazopyrimidinyl group; acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornenyl group, a cyclopentenyl group,a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a fluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a pyrrolyl group, a thiophenyl group, a furanyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, an isoindolylgroup, an indolyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthrolinyl group, a benzoimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzooxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, an imidazopyridinyl group, and animidazopyrimidinyl group, each of which is substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃,—CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid or a salt thereof, a sulfonic acid or a salt thereof, aphosphoric acid or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxygroup, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a fluorenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a pyrrolyl group, athiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a carbazolyl group, a phenanthrolinyl group,a benzoimidazolyl group, a benzofuranyl group, a benzothiophenyl group,an isobenzothiazolyl group, a benzoxazolyl group, an isobenzooxazolylgroup, a triazolyl group, a tetrazolyl group, an oxadiazolyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abenzocarbazolyl group, a dibenzocarbazolyl group, an imidazopyridinylgroup, and an imidazopyrimidinyl group; and —B(Q₆)(Q₇) and—P(═O)(Q₈)(Q₉), wherein Q₆ to Q₉ are each independently selected from aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a naphthylgroup, a pyridinyl group, a pyrimidinyl group, a triazinyl group, and acarbazolyl group; and a phenyl group and a naphthyl group, eachsubstituted with at least one selected from a C₁-C₂₀ alkyl group, aphenyl group, and a naphthyl group.
 31. The organometallic compound ofclaim 27, wherein any substituent on L₁, R₁₁, R₁₃, and R₁₄ in Formula 2Bare each independently selected from a hydrogen, a deuterium, —F, acyano group, a nitro group, —SF₅, —CH₃, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a group represented by Formulas 9-1 to 9-17, and a grouprepresented by Formulas 10-1 to 10-16, and R₁₂ in Formula 2B is selectedfrom the group represented by Formulas 9-1 to 9-17 and groupsrepresented by Formulas 10-1 to 10-16:


32. The organometallic compound of claim 27, wherein L₁ is a ligandrepresented by Formula 2-1 or 2-112:

wherein Z₁ and Z₂, in Formulas 2-1 and 2-112 are each independentlyselected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, —SF₅, ahydroxyl group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —N(Q₁)(Q₂), —Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and—P(═O)(Q₈)(Q₉), wherein Q₁ to Q₉ are each independently selected from ahydrogen, a deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from a C₁-C₆₀ alkyl group and aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup and a monovalent non-aromatic condensed heteropolycyclic group,aa4 and ab4 are each independently selected from, 1, 2, 3, and 4, * and*′ indicate binding sites to M, and wherein at least one of substituentsof the substituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenylgroup, the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substitutedC₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenylgroup, the substituted C₁-C₁₀ heterocycloalkenyl group, the substitutedC₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, the substitutedC₆-C₆₀ arythio group, the substituted C₁-C₆₀ heteroaryl group, thesubstituted a monovalent non-aromatic condensed polycyclic group having8 to 60 carbon atoms, and the substituted monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms is selectedfrom: a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group,each substituted with at least one selected from a deuterium, —F, —Cl,—Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₁-C₁₀cycloalkenyl group, a C₂-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₂-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic grouphaving 8 to 60 carbon atoms, a monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms, —N(Q₁₁)(Q₁₂),—Si(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), and —P(═O)(Q₁₈)(Q₁₉); a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group having 8 to 60 carbonatoms, and a monovalent non-aromatic condensed heteropolycyclic grouphaving 1 to 60 carbon atoms; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, anda monovalent non-aromatic condensed heteropolycyclic group having 1 to60 carbon atoms, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkenyl group, a C₁-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), and—P(═O)(Q₂₈)(Q₂₉); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅) —B(Q₃₆)(Q₃₇), and—P(═O)(Q₃₈)(Q₃₉); wherein Q₁₁ to Q₁₉, (Q₂₁) to Q₂₉, and Q₃₁ to Q₃₉ areeach independently selected from a hydrogen, a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from a C₁-C₆₀ alkyl group and aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms.
 33. Theorganometallic compound of claim 27, wherein L₁ in Formula 1 is selectedfrom ligands represented by Formulas 2-1(1) to 2-1(18):

wherein in Formulas 2-1(1) to 2-1(18), Z₁, Z_(1a), Z_(1b), Z_(1c),Z_(1d), Z₂, Z_(2a), Z_(2b), Z_(2c), and Z_(2d) are each independentlyselected from a deuterium, —F, —Cl, —Br, —I, —SF₅, a hydroxyl group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid or a salt thereof, a sulfonic acid ora salt thereof, a phosphoric acid or a salt thereof, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group having 8 to 60 carbonatoms, a substituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group having 1 to 60 carbon atoms, —N(Q₁)(Q₂),—Si(Q₃)(Q₄)(Q₅), —B(Q₆)(Q₇), and —P(═O)(Q₈)(Q₉), wherein Q₁ to Q₉ areeach independently selected from a hydrogen, a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from a C₁-C₆₀ alkyl group and aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms, whereinnone of Z₁, Z₂, Z_(1a), Z_(1b), Z_(1c), Z_(1d), Z_(2a), Z_(2b), Z_(2c),and Z_(2d) are hydrogen, * and *′ indicate binding sites to M, andwherein at least one of substituents of the substituted C₁-C₆₀ alkylgroup, the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀alkynyl group, the substituted C₁-C₆₀ alkoxy group, the substitutedC₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group,the substituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arythio group,the substituted C₁-C₆₀ heteroaryl group, the substituted a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, andthe substituted monovalent non-aromatic condensed heteropolycyclic grouphaving 1 to 60 carbon atoms is selected from: a deuterium, —F, —Cl, —Br,—I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid or a salt thereof, asulfonic acid or a salt thereof, a phosphoric acid or a salt thereof, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, anda C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted withat least one selected from a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H,—CDH₂, —CF₃, —CF₂H, —CFH₂, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid or a salt thereof, a sulfonic acid or a saltthereof, a phosphoric acid or a salt thereof, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₁-C₁₀ cycloalkenyl group, a C₂-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₂-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₁₁)(Q₁₂), —Si(Q₁₃)(Q₁₄)(Q₁₅), —B(Q₁₆)(Q₁₇), and—P(═O)(Q₁₈)(Q₁₉); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms, and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms; a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group having 8 to 60 carbonatoms, and a monovalent non-aromatic condensed heteropolycyclic grouphaving 1 to 60 carbon atoms, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H,—CFH₂, a hydroxyl group, a cyano group, a nitro group, an amino group,an amidino group, a hydrazine group, a hydrazone group, a carboxylicacid or a salt thereof, a sulfonic acid or a salt thereof, a phosphoricacid or a salt thereof, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkenyl group, aC₁-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group having 8 to 60 carbon atoms, amonovalent non-aromatic condensed heteropolycyclic group having 1 to 60carbon atoms, —N(Q₂₁)(Q₂₂), —Si(Q₂₃)(Q₂₄)(Q₂₅), —B(Q₂₆)(Q₂₇), and—P(═O)(Q₂₈)(Q₂₉); and —N(Q₃₁)(Q₃₂), —Si(Q₃₃)(Q₃₄)(Q₃₅) —B(Q₃₆)(Q₃₇), and—P(═O)(Q₃₈)(Q₃₉); wherein Q₁₁ to Q₁₉, Q₂₁ to Q₂₉, and Q₃₁ to Q₃₉ areeach independently selected from a hydrogen, a deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from a C₁-C₆₀ alkyl group and aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup having 8 to 60 carbon atoms and a monovalent non-aromaticcondensed heteropolycyclic group having 1 to 60 carbon atoms.
 34. Theorganometallic compound of claim 27, wherein L₂ is selected from ligandsrepresented by Formulas 2B-8 to 2B-10:

wherein Formulas 2B-8 to 2B-10, R₁ to R₃ are each independently selectedfrom a methyl group, an ethyl group, an n-propyl group, an isopropylgroup, an n-butyl group, an isobutyl group, a sec-butyl group, atert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentylgroup, and a tert-pentyl group, each of which is unsubstituted; and amethyl group, an ethyl group, an n-propyl group, an isopropyl group, ann-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group,an n-pentyl group, an isopentyl group, a sec-pentyl group, and atert-pentyl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, —CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, ahydroxyl group, a cyano group, a nitro group, an amino group, an amidinogroup, a hydrazine group, a hydrazone group, a carboxylic acid or a saltthereof, a sulfonic acid or a salt thereof, a phosphoric acid or a saltthereof, and a C₁-C₁₀ alkyl group, R₁₁ and R₁₃ to R₁₇ are eachindependently a deuterium, —F, a cyano group, a nitro group, —SF₅, amethyl group, an ethyl group, an n-propyl group, an isopropyl group, ann-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group,an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentylgroup, an n-hexyl group, an isohexyl group, a sec-hexyl group, atert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptylgroup, a tert-heptyl group, an n-octyl group, an isooctyl group, asec-octyl group, a tert-octyl group, an n-nonyl group, an isononylgroup, a sec-nonyl group, a tert-nonyl group, an n-decyl group, anisodecyl group, a sec-decyl group, a tert-decyl group, a methoxy group,an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctylgroup, an adamantanyl group, a norbornenyl group, a cyclopentenyl group,a cyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group, each of which isunsubstituted; a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group,a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentylgroup, a tert-pentyl group, an n-hexyl group, an isohexyl group, asec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptylgroup, a sec-heptyl group, a tert-heptyl group, an n-octyl group, anisooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group,an isononyl group, a sec-nonyl group, a tert-nonyl group, an n-decylgroup, an isodecyl group, a sec-decyl group, a tert-decyl group, amethoxy group, an ethoxy group, a propoxy group, a butoxy group, apentoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptylgroup, a cyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup, each substituted with at least one selected from a deuterium, —F,—CD₃, —CD₂H, —CDH₂, —CF₃, —CF₂H, —CFH₂, a cyano group, a nitro group, aC₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group; and —B(Q₆)(Q₇) and—P(═O)(Q₈)(Q₉), wherein Q₆ to Q₉ are each independently selected from aC₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, and anaphthyl group; and a phenyl group and a naphthyl group, eachsubstituted with at least one selected from a C₁-C₁₀ alkyl group, aphenyl group, and a naphthyl group, and wherein R₁₂ is selected from anethyl group, an n-propyl group, an isopropyl group, an n-butyl group, anisobutyl group, a sec-butyl group, a tert-butyl group, an n-pentylgroup, an isopentyl group, a sec-pentyl group, a tert-pentyl group, ann-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group,an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptylgroup, an n-octyl group, an isooctyl group, a sec-octyl group, atert-octyl group, an n-nonyl group, an isononyl group, a sec-nonylgroup, a tert-nonyl group, an n-decyl group, an isodecyl group, asec-decyl group, a tert-decyl group, an ethoxy group, a propoxy group, abutoxy group, a pentoxy group, a cyclopentyl group, a cyclohexyl group,a cycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group, each of which is unsubstituted; a methylgroup and a methoxy group, each substituted with at least one selectedfrom a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclooctyl group, an adamantanyl group, a norbornenyl group, acyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, aphenyl group, a naphthyl group, a pyridinyl group, and a pyrimidinylgroup; and an ethyl group, an n-propyl group, an isopropyl group, ann-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group,an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentylgroup, an n-hexyl group, an isohexyl group, a sec-hexyl group, atert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptylgroup, a tert-heptyl group, an n-octyl group, an isooctyl group, asec-octyl group, a tert-octyl group, an n-nonyl group, an isononylgroup, a sec-nonyl group, a tert-nonyl group, an n-decyl group, anisodecyl group, a sec-decyl group, a tert-decyl group, an ethoxy group,a propoxy group, a butoxy group, a pentoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclooctyl group, anadamantanyl group, a norbornenyl group, a cyclopentenyl group, acyclohexenyl group, a cycloheptenyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group, each substituted withat least one selected from a deuterium, —F, —CD₃, —CD₂H, —CDH₂, —CF₃,—CF₂H, —CFH₂, a cyano group, a nitro group, a C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclooctyl group, an adamantanyl group, anorbornenyl group, a cyclopentenyl group, a cyclohexenyl group, acycloheptenyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group.
 35. An organic light-emitting devicecomprising: a first electrode; a second electrode; and an organic layerthat is disposed between the first electrode and the second electrodeand which comprises an emission layer, wherein the organic layercomprises the organometallic compound of claim 27.